iM 4,1-14,4 2011 iMac Graphics Card Upgrade

[dorninko]

I finally bought a WX 4130 card from the eBay account I linked yesterday.

I was a bit hesitating but I just received a notification from an application I'm using that they'll stop working on September the 1st on my browser, and I cannot install anything more recent on High Sierra, so it's definitely time to upgrade !

Thank you all for your help, I'll post something once the upgrade is done (or if it fails ).

If you use all the knowledge form this forum then you should be successful with the wx4130.
btw, have you tried another browser? in High Sierra Safari is well outdated (no updates from Apple) but Chrome or Firefox work usually much better.

 

[mathieudel]

If you use all the knowledge form this forum then you should be successful with the wx4130.
btw, have you tried another browser? in High Sierra Safari is well outdated (no updates from Apple) but Chrome or Firefox work usually much better.

For High Sierra, latest available browser versions are:

• Firefox: 115.14.0 ESR (the one I use)
• Safari 13.1.2
• Chrome 116 (I avoid it like the plague)
• Opera I'm not sure. I have 102.0.4880.78 working, and IIRC I did search their download history to get the latest compatible version when I installed it. It is based on Chromium 116, so I believe is equivalent to Chrome 116.

The application I use (Slack) will drop support for Firefox versions <= 117, Safari <= 16 and Chrome <= 116.
For the standalone client, they killed macOS 10.15 last year and are about to kill macOS 11 (what could have been installed even without the new GPU).

Looks like I'm doomed !

 

[MrZupp]

Does anyone have any info on the RX6600M MXM variant?

Saw one for sale and I'm interested in buying it for my 12,2.

 

[ChiliConQueso]

So finally got around to trying to upgrade my graphics card to a wx4150. I installed it along with the copper shim into my iMac and made a sonoma installer via OCLP. The directions I got from the ebay seller I got my card from mentioned having the EFI and system files he provided on a USB and plugging that in and choosing EFI boot. Turn off the iMac and plug in your SSD and then let it boot. I (hopefully) installed sonoma via OCLP and now I get a black display after the apple logo appears dimly on the screen. Is there a way for me to remotely connect to the iMac like on my network? Like realistically what do I need to do to actually get my display to work? I already got a miniDP dummy and that didn't help, I have a second monitor and that also doesn't get anything. The only time it displayed anything what when I ran disk utility to wipe the SSD. I really hope I won't have to take out the new card, put the old one in, reinstall high sierra, use OCLP to install sonoma, and then put the new one in again cuz that would be a major PITA. Any help would be awesome!

 

[howardc64]

So finally got around to trying to upgrade my graphics card to a wx4150. I installed it along with the copper shim into my iMac and made a sonoma installer via OCLP. The directions I got from the ebay seller I got my card from mentioned having the EFI and system files he provided on a USB and plugging that in and choosing EFI boot.

When you booted seller provided USB files, what did you get? Apple logo -> some macOS installer? Presumably seller is supplying properly made USB files to check HW installation was correct.

Turn off the iMac and plug in your SSD and then let it boot. I (hopefully)

What was on your SSD? High Sierra?

installed sonoma via OCLP

How did you install OCLP Sonoma?

and now I get a black display after the apple logo appears dimly on the screen. Is there a way for me to remotely connect to the iMac like on my network? Like realistically what do I need to do to actually get my display to work? I already got a miniDP dummy and that didn't help, I have a second monitor and that also doesn't get anything. The only time it displayed anything what when I ran disk utility to wipe the SSD. I really hope I won't have to take out the new card, put the old one in, reinstall high sierra, use OCLP to install sonoma, and then put the new one in again cuz that would be a major PITA. Any help would be awesome!

First, your install sequence is unclear and unfamiliar to the process I use (see signature link for many procedure outlines)

Also since you got the pre-flashed GPU, seller provided EFI and system files, they are potentially the problem since its unknown. My aliexpress pre-flashed M5100 had wrong VBIOS flashed.

A couple of tips to avoid removing wx4150 but this assumes hardware is good (properly working, any mods etc)

• GPU VBIOS can be reflashed using GRML on USB stick without removal. Just need to have no bootable volume on the SATA SSD (or any SATA channel).
• Building installation USB is easy enough with OCLP app. Look at the many online directions available. Just need to set the correct build target model (since making OCLP USB on an alternate Mac) AMD_GOP_Injection and AMD_Polaris. This will build you a known OCLP USB boot/install stick

If VBIOS is correct, OCLP USB stick is correct, and SSD has no bootable volume. It will boot to apple logo -> USB Sonoma installer all displaying properly. From there, just install Sonoma to blank SSD like any macOS Recovery.

Can see all the info in my signature links.

 

[ChiliConQueso]

When you booted seller provided USB files, what did you get? Apple logo -> some macOS installer? Presumably seller is supplying properly made USB files to check HW installation was correct.



What was on your SSD? High Sierra?



How did you install OCLP Sonoma?



First, your install sequence is unclear and unfamiliar to the process I use (see signature link for many procedure outlines)

Also since you got the pre-flashed GPU, seller provided EFI and system files, they are potentially the problem since its unknown. My aliexpress pre-flashed M5100 had wrong VBIOS flashed.

A couple of tips to avoid removing wx4150 but this assumes hardware is good (properly working, any mods etc)

• GPU VBIOS can be reflashed using GRML on USB stick without removal. Just need to have no bootable volume on the SATA SSD (or any SATA channel).
• Building installation USB is easy enough with OCLP app. Look at the many online directions available. Just need to set the correct build target model (since making OCLP USB on an alternate Mac) AMD_GOP_Injection and AMD_Polaris. This will build you a known OCLP USB boot/install stick

If VBIOS is correct, OCLP USB stick is correct, and SSD has no bootable volume. It will boot to apple logo -> USB Sonoma installer all displaying properly. From there, just install Sonoma to blank SSD like any macOS Recovery.

Can see all the info in my signature links.

So actually I was able to finally get it to boot! Apparently the install wasn't fully completed (an apparent problem with sonoma, not limited to just OCLP and older unsupported Macs). My problem now is not having a backlight on my LCD still. Even with the dummy miniDP still no backlight. I'm able to remote onto the iMac from my macbook. Everything (besides the backlight and Wifi module that I also changed) is working fine now! Any tips for how to fix the backlight issue? It also shows as Polaris 4gb card in system info

 

[Vladistone]

So actually I was able to finally get it to boot! Apparently the install wasn't fully completed (an apparent problem with sonoma, not limited to just OCLP and older unsupported Macs). My problem now is not having a backlight on my LCD still. Even with the dummy miniDP still no backlight. I'm able to remote onto the iMac from my macbook. Everything (besides the backlight and Wifi module that I also changed) is working fine now! Any tips for how to fix the backlight issue? It also shows as Polaris 4gb card in system info

There are several possible reasons for this behavior of the iMac:
- faulty screen backlight (you could accidentally hit the corner of the LCD during dismantling or installation, and as a result, fragile bus contacts fell off on the diode strip)
- you could install the wrong Vbios firmware (try to check all your steps for reflashing the card again!)
- you have problems with the Vcard (you can find out if you check all the previous points)

 

[ChiliConQueso]

There are several possible reasons for this behavior of the iMac:
- faulty screen backlight (you could accidentally hit the corner of the LCD during dismantling or installation, and as a result, fragile bus contacts fell off on the diode strip)
- you could install the wrong Vbios firmware (try to check all your steps for reflashing the card again!)
- you have problems with the Vcard (you can find out if you check all the previous points)

I actually just went through the process of using GRML to flash the vbios with the WX4150_GOP.ROM and succeeded. However, still no backlight on bootup Is this common? Once I do OCLP to install Sonoma will it gain backlight function or is there some other vbios I need to put on the card? I'm sure I can go through the frustration of redoing my OCLP install, but I'd just like to know what the heck is the deal haha.

 

[howardc64]

I actually just went through the process of using GRML to flash the vbios with the WX4150_GOP.ROM and succeeded. However, still no backlight on bootup Is this common? Once I do OCLP to install Sonoma will it gain backlight function or is there some other vbios I need to put on the card? I'm sure I can go through the frustration of redoing my OCLP install, but I'd just like to know what the heck is the deal haha.

Do the simple step to verify GPU card, VBIOS are all functional

• disconnect SATA SSD
• make Sonoma USB installer with all correct settings in bottom of post #21955 and OC installed into USB stick EFI.
• Insert USB stick and boot iMac, you should see image (with backlight) Sonoma USB installer boot option.

Backlight will turn on just booting OC from USB EFI partition. Disconnect the SATA SSD to force it to boot OC from USB EFI.

 

[internetzel]

I actually just went through the process of using GRML to flash the vbios with the WX4150_GOP.ROM and succeeded. However, still no backlight on bootup Is this common? Once I do OCLP to install Sonoma will it gain backlight function or is there some other vbios I need to put on the card? I'm sure I can go through the frustration of redoing my OCLP install, but I'd just like to know what the heck is the deal haha.

Using one of the VBIOSes linked on the first page if this thread, the backlight will be switched on. You can verify the missing backlight by illuminating the screen using a flash light. If you see the screen contents using the flash light, you've got some hardware problem, hopefully just forgot to connect the backlight cable.

 

[ChiliConQueso]

Using one of the VBIOSes linked on the first page if this thread, the backlight will be switched on. You can verify the missing backlight by illuminating the screen using a flash light. If you see the screen contents using the flash light, you've got some hardware problem, hopefully just forgot to connect the backlight cable.

I might have just used the default vBIOS provided in the GRML download that I got from here. I can try to use the one linked for the WX4150 that the table in the first post. I wiped my SSD and made a new USB installer for OCLP. Still no backlight even when just the OC USB in. After installing Sonoma, I will unplug my ssd and the OC USB and redo my GRML vBIOS update with the GOP from the first post like I said. I would be really sad if it was a hardware thing, I was super careful taking out the panel and undoing all the connections, and it worked perfectly fine before taking the graphics card out and replacing it (I have electronics experience, just a newbie when it comes to working on the macs haha). I guess we'll see once Sonoma is done and I reflash if my problem will be solved or what. Worst case I did see some people were able to replace the LED strip/ solder wires directly to it if that connector in the corner was broken so I'd have to do that as well.

 

[howardc64]

Worst case I did see some people were able to replace the LED strip/ solder wires directly to it if that connector in the corner was broken so I'd have to do that as well.

LED strip connector reflow is a major effort. My guide here. Putting original GPU card back and power on iMac to see if have backlight would be far easier.

And do flashlight test to confirm LCD is displaying properly to confirm just backlight out per @internetzel suggestion

 

[ChiliConQueso]

LED strip connector reflow is a major effort. My guide here. Putting original GPU card back and power on iMac to see if have backlight would be far easier.

And do flashlight test to confirm LCD is displaying properly to confirm just backlight out per @internetzel suggestion

Using a flashlight I can see the screen so it is working, it's just the backlight that's not working. Could it be the vBIOS making it not work I'm currently waiting for Sonoma to install before I unplug and do GRML to flash it again.

 

[howardc64]

Using a flashlight I can see the screen so it is working, it's just the backlight that's not working. Could it be the vBIOS making it not work I'm currently waiting for Sonoma to install before I unplug and do GRML to flash it again.

No need to install Sonoma to see backlight working. Just insert installer USB stick with properly configured OC EFI (what you get when you click "Build and Install Open Core" on OCLP app with correct configurations and write it to the USB stick) If hardware is working, correct VBIOS is flashed, SSD is blank, correct OC on USB EFI, iMac will boot USB EFI and backlight will turn on to show OC boot picker.

Maybe a dumb question, I'm assuming panel backlight cable is connected to the backlight board.?

 

[Vladistone]

@ChiliConQueso
a couple more stupid questions:
- did you do all the recommendations that @internetzel and @howardc64 recommended?
1. runned the OS from USB? but not from the built-in SDD...
- have you used before the early or previos OS for update the iMac?
- have you used before the alternative vBIOS GOP firmware?
2. checked the LED power connection...
if you had excluded all these reasons, than it would be possible to give further advice on troubleshooting... But you stubbornly do not want to follow the recommendations and insist that with software and the update went perfectly...
Well, I can say that you are wrong, since there can be many hard&software reasons for the backlight failure, and listing them means doing all the dirty work for you by re-studying this forum...

the only thing that can be logically generalized:
you have no power on the LED bus and the chain of reasons is as follows:
1. no power is supplied to the inverter from the PSU *may be as a HW as SW reasons
2. no command is sent to turn on the power of the display inverter or to the PWM control unit of the LED backlight *SW reasons too
3. the inverter is faulty *HW reason and so on
4. there is no connection at the inverter output to the display (this is a very common problem when the synchronization connection socket is accidentally broken off or partially break one of the 4 of socket petals or of this plug)
5. there is no contact in the display itself after power is supplied to the LED bus (this option also often occurs and it is the most labor-intensive to repair and requires experience with disassembling the matrix of TV displays)
6. the two inner LED buses inside the display is faulty... it happens but it is unlikely in your case...

I hope this will help with understanding and organizing the search for the causes of the display backlight malfunction!
IMHO: you are stuck on excluding points 1 or 2... which are key when looking for and recommendations for you...

But the path of the samurai is thorny and long...

 

[ChiliConQueso]

@ChiliConQueso
a couple more stupid questions:
- did you do all the recommendations that @internetzel and @howardc64 recommended?
1. runned the OS from USB? but not from the built-in SDD...
- have you used before the early or previos OS for update the iMac?
- have you used before the alternative vBIOS GOP firmware?
2. checked the LED power connection...
if you had excluded all these reasons, than it would be possible to give further advice on troubleshooting... But you stubbornly do not want to follow the recommendations and insist that with software and the update went perfectly...
Well, I can say that you are wrong, since there can be many hard&software reasons for the backlight failure, and listing them means doing all the dirty work for you by re-studying this forum...

the only thing that can be logically generalized:
you have no power on the LED bus and the chain of reasons is as follows:
1. no power is supplied to the inverter from the PSU *may be as a HW as SW reasons
2. no command is sent to turn on the power of the display inverter or to the PWM control unit of the LED backlight *SW reasons too
3. the inverter is faulty *HW reason and so on
4. there is no connection at the inverter output to the display (this is a very common problem when the synchronization connection socket is accidentally broken off or partially break one of the 4 of socket petals or of this plug)
5. there is no contact in the display itself after power is supplied to the LED bus (this option also often occurs and it is the most labor-intensive to repair and requires experience with disassembling the matrix of TV displays)
6. the two inner LED buses inside the display is faulty... it happens but it is unlikely in your case...

I hope this will help with understanding and organizing the search for the causes of the display backlight malfunction!
IMHO: you are stuck on excluding points 1 or 2... which are key when looking for and recommendations for you...

But the path of the samurai is thorny and long...

Yes prior to trying to upgrade the GPU it was running stock High Sierra from an SSD. The screen functioned and the backlight functioned prior to changing the GPU.
Yes, the power is hooked up to the the screen from the board on the top left, both connectors.
Yes, I just now followed the link for the GOP from the link in the table on the first post of this thread, and GRML'd and flashed the vBIOS with that one, it still does not have a backlight.
The only reason I was trying to just do the Sonoma update again was to be able to remote connect to it with my macbook, but that's also not working and can be solved after the backlight issue is fixed.
If it was a SW problem for power not going to the LEDs how would that be fixed? With a BIOS update to the iMac itself?

 

[Vladistone]

Everything in the first point hat you described above was before the upgrade of computer! and not after... Everything that happened duaring of this:

• A) you dismantled and reassembled the computer elements;
• B) you upgraded vBIOS of Vcard and mounted it into iMac; (correctly? I don't know...)
• C) and also installed OCLP with the formation of a new EFI partition on the SSD;
• D) you inctalled the newest MacOS;

In which of these operations could you have made a mistake? Neither you nor we are sure of anything, and it may be in all !!! Therefore it is necessary to find the error by the "method of exclusion" and fix it...
Earlier you have already been told about options for found outing the problems by running the OS from a OCLP USB Install Stick (remark: * bold text is updated at 04/09/24) - you still haven't done this. Well so what the next?
The troubleshooting method and the sequence of tasks for finding solutions should be as follows:

1. Exclude the possibility of incorrect installation of the OS (IMHO - if you see that the OS is working (the screen does not light only, and the OS still started and interacts with the network and you can work remotely, but it inconveniently condition for investigation of problem). Then the problem is probably not the OS, and then...
2. OCLP installation - here it may help to start the OS installer from OCLP USB Install Stick(remark *updated 04/09/24) with the appropriate exception that you installed the correct patch and vBIOS. but it is possible that at the stage of preparing the USB installer you are doing something wrong again, that is why I asked about the following:
   • 2.1. - did you start the computer with alternative vBIOS or OCLP patches? have a results? - the answer is also "no"!
   • 2.2. - have you tried installing (remark: *updated 04/09/24) the old/native MacOS with new Vcard? for example High Sierra 10.13.6 ... Where the metal characteristics of the new Vcard and the corresponding OCLP patches for running the most recent and unsupported OS Sonoma are not required! As I understand you - you did not do these experiments!
3. have you checked the hardware for correct operation and how? Sorry - no way... Therefore, if the first two points did not lead to a satisfactory result, then you need to look for the problem that arose when opening and remounting the computer parts, namely:
   • 3.1. Look for power for the LEDs of monitor or
   • 3.2 Exclude hardware upgrade and look for reasons in unskilled work on point "A" above (we exclude incorrect operation of the Vcard and OCLP settings by returning the old native card with which you are sure that the computer worked).

Which path you choose is up to you! but only after restoring operability according to the old hardware - you can make sure that the reason isn't in particular the monitor or in the inverter for supply the LEDs or otherwise about except the new Vcard preparation.
Otherwise start from what to repair, if the points above did not help or you localize the reason for the lack of screen backlighting:

• 4. either in a malfunction of the inverter
• 5. or in a malfunction of the LED bus of the display
• 6. or in the supply connections between them...

Sorry for my English please...
With best wishes

 

[howardc64]

Yes, I just now followed the link for the GOP from the link in the table on the first post of this thread, and GRML'd and flashed the vBIOS with that one, it still does not have a backlight.

This is a confusing answer because it doesn't tell what the iMac ran. iMac can run 4 possible bootable partitions (EFI on SATA SSD, EFI on USB, macOS partition on SATA SSD, and macOS partition (usually the installer) on USB) Which one runs depends on several factors. And what is stored in these partition when it boots matter of course. So when you say "GRML flashed XYZ VBIOS and still no backlight" all the info on what the iMac ran is missing.

Actually, there is one method thats even simpler to prove backlight function and ONLY requires flashing VBIOS correctly AND good hardware to have backlight. Any SATA SSD and USB stick contents doesn't matter at all (can be blank, can have any bootable non bootable partitions). The solution is to use EG version of VBIOS. I summarized EG here

iMac+Metal GPU - vBIOS

vBIOS = Video BIOS. Basically how GPU boots. Since used GPU are sourced from PCs, need to be flashed to match how Mac boot. It is a ROM image and need to be flashed into GPU cards onboard EEPROM (reprogrammable ROM store) Some cards don't have this EEPROM (GPU maker cut cost and put file on PC to

sites.google.com

The EG VBIOS link provided include several WX4150 Enable Gop VBIOSes. Looks like there are Hynix and non Hynix variations? I don't know what Adj is for. I don't know which one is correct for your GPU card so do some info search in the thread (I know its a long long thread). I have used 3 different Enable Gop VBIOS for 2 different AMD GPUs (M4000, WX4130) for 3 different iMacs (10,1 LVDS, 10,1 eDP, 12,2) and EG VBIOS is hugely beneficial in many usages including searching for your problem.

Benefit of running an EG VBIOS is you can just press option key (do on an Apple keyboard to be certain) when powering on the iMac, boot menu will appear to show what is on SATA and USB that is bootable (including the EFI partitions). What is important for you is it will turn on the backlight and only depend on getting 2 things correct 1) hardware is good 2) Correct VBIOS flashed. Again, what is on SATA SSD and USB stick doesn't matter and doesn't affect backlight turning on.

Here is a video of my 12,2 booting holding down option key (on Apple Magic keyboard 2 connected by lightning to USB cord to iMac since BT connection doesn't work during the boot stage) iMac powers up, chime sound, backlight on, with option key pressed, 4 bootable partition shows up (2 from SATA SSD, 2 from USB installer)

Correct VBIOS flashing is still required in this simplest method to show backlight is working. Post GRML text screen showing flashing the WX4150 Enable Gop VBIOS so experts here can confirm proper VBIOS flashing. They can see ROM name, see flash tool complete with verification output etc. Also post picture of your wx4150 so experts have all the details.

 

[ChiliConQueso]

This is a confusing answer because it doesn't tell what the iMac ran. iMac can run 4 possible bootable partitions (EFI on SATA SSD, EFI on USB, macOS partition on SATA SSD, and macOS partition (usually the installer) on USB) Which one runs depends on several factors. And what is stored in these partition when it boots matter of course. So when you say "GRML flashed XYZ VBIOS and still no backlight" all the info on what the iMac ran is missing.

Actually, there is one method thats even simpler to prove backlight function and ONLY requires flashing VBIOS correctly AND good hardware to have backlight. Any SATA SSD and USB stick contents doesn't matter at all (can be blank, can have any bootable non bootable partitions). The solution is to use EG version of VBIOS. I summarized EG here

iMac+Metal GPU - vBIOS

vBIOS = Video BIOS. Basically how GPU boots. Since used GPU are sourced from PCs, need to be flashed to match how Mac boot. It is a ROM image and need to be flashed into GPU cards onboard EEPROM (reprogrammable ROM store) Some cards don't have this EEPROM (GPU maker cut cost and put file on PC to

sites.google.com

The EG VBIOS link provided include several WX4150 Enable Gop VBIOSes. Looks like there are Hynix and non Hynix variations? I don't know what Adj is for. I don't know which one is correct for your GPU card so do some info search in the thread (I know its a long long thread). I have used 3 different Enable Gop VBIOS for 2 different AMD GPUs (M4000, WX4130) for 3 different iMacs (10,1 LVDS, 10,1 eDP, 12,2) and EG VBIOS is hugely beneficial in many usages including searching for your problem.

Benefit of running an EG VBIOS is you can just press option key (do on an Apple keyboard to be certain) when powering on the iMac, boot menu will appear to show what is on SATA and USB that is bootable (including the EFI partitions). What is important for you is it will turn on the backlight and only depend on getting 2 things correct 1) hardware is good 2) Correct VBIOS flashed. Again, what is on SATA SSD and USB stick doesn't matter and doesn't affect backlight turning on.

Here is a video of my 12,2 booting holding down option key (on Apple Magic keyboard 2 connected by lightning to USB cord to iMac since BT connection doesn't work during the boot stage) iMac powers up, chime sound, backlight on, with option key pressed, 4 bootable partition shows up (2 from SATA SSD, 2 from USB installer)

View attachment 2411799View attachment 2411800

Correct VBIOS flashing is still required in this simplest method to show backlight is working. Post GRML text screen showing flashing the WX4150 Enable Gop VBIOS so experts here can confirm proper VBIOS flashing. They can see ROM name, see flash tool complete with verification output etc. Also post picture of your wx4150 so experts have all the details.

@Vladistone I stopped trying to redownload the OS onto the SSD. I also don't have the SSD installed, I have it connected via USB to the back as it is easier to access right now while troubleshooting, and is currently not plugged in.
I have OCLP with Sonoma installed on a USB that I've tried booting from and still don't get the backlight.
I've tried 2 different USBs that I went through and separately built OCLP on, making sure that when I build it I select iMac 12,1.
No, I have not tried to run it on High Sierra again, I may end up having to do that before I try switching the graphics cards again.
Yes in the worst case I'd have to take it all apart again, and make sure it's properly installed/ need to put the original card back in to see if that's the issue, it's just something I'd like to avoid as (not to make excuses) I'm just really busy and can't afford to spend a large amount of time doing this. It's something I can do a bit at a time, but dumping hours into it a day is not something doable with my current schedule.
And I also want to say thank you for taking the time to respond and try to narrow in on stuff that I may have missed/ just don't know about. New to working on macs, way more used to just replacing bad components on circuit boards and the like and Windows PCs.

@howardc64 after reflashing the vBIOS for the WX4150 using GRML remotely, I then tried to use the USB installer built with OCLP 1.5.0 for MacOS Sonoma to boot from and still didn't get a backlight.

I may end up going with an EG vBIOS, I'll need to look more into it.

I've also attached the screenshot of GRML flashing the WX4150.

And thank you as well howard for your explanations and help during all this! I just want a working iMac! haha

 

[howardc64]

@Vladistone I stopped trying to redownload the OS onto the SSD. I also don't have the SSD installed,

Can I confirm if you have internal SATA SSD connected? or is the SSD blank? (what do you mean by don't have it installed) This is important because IF there is a bootable EFI partition on the internal SATA SSD, iMac will try to boot that first before USB EFI with OC. You want to eliminate this variable.

I have it connected via USB to the back as it is easier to access right now while troubleshooting, and is currently not plugged in.
I have OCLP with Sonoma installed on a USB

Please confirm this is how you made the USB stick

1. On another mac
2. Set target model to 12,1 ( your post #21883 )
3. ticked AMD_GOP_Injection and selected AMD Polaris
4. Clicked and completed Created macOS Installer button on OCLP app (download Sonoma, write installer to USB stick)
5. Clicked and completed "Build and Install OpenCore" button on OCLP app (create OC per target model and AMD options and write into USB stick as an EFI partition)

IF this is how you made the USB stick. It is commonly referred to as OCLP USB Install Stick.
This stick doesn't have macOS installed on it. It has macOS installer installed on it. Technically speaking, the installer is a light version of the macOS running to installed the full macOS/

The key is you want to boot the OC in USB EFI made in step 5. This OC is configured to work with the specific GPU and flashed VBIOS. They have to match to make working.

@howardc64 after reflashing the vBIOS for the WX4150 using GRML remotely, I then tried to use the USB installer built with OCLP 1.5.0 for MacOS Sonoma to boot from and still didn't get a backlight.

I may end up going with an EG vBIOS, I'll need to look more into it.

If you made OCLP USB Install Stick as noted above AND internal SATA SSD is disconnected (or blank with no EFI partition), then iMac will boot the OC on the USB EFI. Backlight will turn on if VBIOS + OC are all made properly and hardware is good.

If you flash EG VBIOS, then OCLP USB Install Stick doesn't matter anymore so its simpler in case you are making it incorrectly. Just press option key when powering up iMac. Backlight will turn on IF hardware is good and correct EG VBIOS is flashed.

I've also attached the screenshot of GRML flashing the WX4150.

This looks generally correct. But you need to show picture of your GPU (both sides) I guess if you don't have previous picture this maybe difficult as its installed already under the logic board. The VBIOS shows a HynixAJR version, need to confirm which is the VRAM vendor and if Hynix, the model # is AJR. Maybe its possible to see this with just the screen removed.

 

[ChiliConQueso]

Can I confirm if you have internal SATA SSD connected? or is the SSD blank? (what do you mean by don't have it installed) This is important because IF there is a bootable EFI partition on the internal SATA SSD, iMac will try to boot that first before USB EFI with OC. You want to eliminate this variable.



Please confirm this is how you made the USB stick

1. On another mac
2. Set target model to 12,1 ( your post #21883 )
3. ticked AMD_GOP_Injection and selected AMD Polaris
4. Clicked and completed Created macOS Installer button on OCLP app (download Sonoma, write installer to USB stick)
5. Clicked and completed "Build and Install OpenCore" button on OCLP app (create OC per target model and AMD options and write into USB stick as an EFI partition)

View attachment 2412024View attachment 2412025

IF this is how you made the USB stick. It is commonly referred to as OCLP USB Install Stick.
This stick doesn't have macOS installed on it. It has macOS installer installed on it. Technically speaking, the installer is a light version of the macOS running to installed the full macOS/

The key is you want to boot the OC in USB EFI made in step 5. This OC is configured to work with the specific GPU and flashed VBIOS. They have to match to make working.



If you made OCLP USB Install Stick as noted above AND internal SATA SSD is disconnected (or blank with no EFI partition), then iMac will boot the OC on the USB EFI. Backlight will turn on if VBIOS + OC are all made properly and hardware is good.

If you flash EG VBIOS, then OCLP USB Install Stick doesn't matter anymore so its simpler in case you are making it incorrectly. Just press option key when powering up iMac. Backlight will turn on IF hardware is good and correct EG VBIOS is flashed.



This looks generally correct. But you need to show picture of your GPU (both sides) I guess if you don't have previous picture this maybe difficult as its installed already under the logic board. The VBIOS shows a HynixAJR version, need to confirm which is the VRAM vendor and if Hynix, the model # is AJR. Maybe its possible to see this with just the screen removed.

I have a SATA to USB adapter, so the SSD is not even installed in the Mac, it's just plugged in to the USB in the back.

Yes for the OCLP USB Install Stick I did it on my M1 Macbook Air, set the target to be a 12,1 and selected both the AMD_GOP_Injection and AMD Polaris card options in Advanced.

I actually went back a bit in the forums and saw that @Ausdauersportler had a GOP for the WX4150 with HyinxAJR. I just used GRML to flash that onto the card and am still not getting a backlight. However before that I had used the GOP that's linked on the first post of this thread, and it actually made me get no display at all! So I'm back to square one with no backlight, but at least the display still works.

I'll also note that I'm getting the 3 lights on the motherboard, which I believe is a good sign from what I've seen on here.

I don't think I could get a pic of the GPU without disassembly, as it's on the back part of the motherboard.

Also just redid to be sure the OCLP USB Install Stick and held option, chose the EFI boot option and still no backlight.

 

[howardc64]

I have a SATA to USB adapter, so the SSD is not even installed in the Mac, it's just plugged in to the USB in the back.

What is plugged into internal SATA? Original HDD? What is on its EFI and macOS partition? I ask because if there is a valid EFI and macOS partition there, then iMac will boot that as first priority and never use EFI from the OCLP USB Installer (which is what you want) This is the reason I keep explaining.. disconnect any bootable drive on internal SATA. Now I also learn you have external USB SATA driver, disconnect that too. Disconnect every drive except for OC USB installer. You only want to boot OC EFI on the USB installer so it talks to the GPU VBIOS while trying to resolve your backlight issue.

Also in general, I've not had much luck installing OCLP to external drive via USB2. Thus I always install to SSD to internal SATA. Anyway, you are not this far yet.

Also just redid to be sure the OCLP USB Install Stick and held option, chose the EFI boot option and still no backlight.

If you don't flash EG VBIOS, holding down option will not do anything. No backlight, no booting.

 

[ChiliConQueso]

What is plugged into internal SATA? Original HDD? What is on its EFI and macOS partition? I ask because if there is a valid EFI and macOS partition there, then iMac will boot that as first priority and never use EFI from the OCLP USB Installer (which is what you want) This is the reason I keep explaining.. disconnect any bootable drive on internal SATA. Now I also learn you have external USB SATA driver, disconnect that too. Disconnect every drive except for OC USB installer. You only want to boot OC EFI on the USB installer so it talks to the GPU VBIOS while trying to resolve your backlight issue.

Also in general, I've not had much luck installing OCLP to external drive via USB2. Thus I always install to SSD to internal SATA. Anyway, you are not this far yet.



If you don't flash EG VBIOS, holding down option will not do anything. No backlight, no booting.

The SSD is plugged in via USB, there is no harddrive inside the iMac. When I did it I made sure nothing except the OC USB Installer was connected.

 

[Vladistone]

If you flash EG VBIOS, then OCLP USB Install Stick doesn't matter anymore so its simpler in case you are making it incorrectly. Just press option key when powering up iMac. Backlight will turn on IF hardware is good and correct EG VBIOS is flashed.

@howardc64
I believe that this is the simplest way to find out the functionality of the backlight and the entire power supply chain from the inverter to the monitor. After this procedure, it will be immediately clear whether there is a need to carry out again the hardware inspection by iMac dismount or not!!!

Perfect! bellissimo!
😇

 

[howardc64]

The SSD is plugged in via USB, there is no harddrive inside the iMac. When I did it I made sure nothing except the OC USB Installer was connected.

Helpful to know.

Here are the search results for wx4150 in this thread

https://forums.macrumors.com/search/4739571/?page=25&q=wx4150&t=post&c[thread]=1596614&o=relevance

Post #11784 is particularly interesting. Sounds like wx4150 has components that easily contact the heatsink and cause a short (and black screen) You can read through his experience in 2020. Note back in 2020, all the software (OCLP etc) was probably less integrated.