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I recently bought an iMac 27" from Mid 2010 (i5, 12GB RAM, HD5750, 512GB SSD). The seller stated that the GPU was damaged (which was stated by a professional he gave it to). When I power up the iMac just the fans start up but there is no image at all, is this normal for a bad GPU?

My next question is: I wanted to update the iMac to Big Sur. So I'll need a Metal GPU and was thinking about the WX4170 as it seems to be a pretty straight forward option after reading the guide here. Now I still have a question. Is it possible for me to install the WX4170 and get an image straight away or does the GPU need to be flashed first to get any image at all?
I don't have any other macs at home where I could install it to flash it.

This is my first Apple device btw, I tried to read a lot in these forums but not everything is 100% clear to me yet o_O
 
I recently bought an iMac 27" from Mid 2010 (i5, 12GB RAM, HD5750, 512GB SSD). The seller stated that the GPU was damaged (which was stated by a professional he gave it to). When I power up the iMac just the fans start up but there is no image at all, is this normal for a bad GPU?

My next question is: I wanted to update the iMac to Big Sur. So I'll need a Metal GPU and was thinking about the WX4170 as it seems to be a pretty straight forward option after reading the guide here. Now I still have a question. Is it possible for me to install the WX4170 and get an image straight away or does the GPU need to be flashed first to get any image at all?
I don't have any other macs at home where I could install it to flash it.

This is my first Apple device btw, I tried to read a lot in these forums but not everything is 100% clear to me yet o_O

I have this same iMac and had the HD5750. I followed the posts by davidg5678 and successfully upgraded earlier this year to the same WX4150 that he did. Here is the link: davidg5678 2010 iMac WX4150

Very happy with the WX4150 which is reported as an RX460 4GB on mine. If you take your time and follow the steps carefully you will have a good chance for success with the WX4150, not sure about the 4170 since I have no experience with that gpu. I am running Big Sur 11.5.2 using OCLP 0.2.5 and could not be happier with this now ten year old iMac.

Note about your stock HD5750: this was a solid gpu not known for failures like other AMD gpus of that era. I would suggest investigating getting that gpu working first before ordering any upgrade gpu by opening the iMac and disassembling to the HD5750 MXM module. It is possible the module has become loose or unseated in the MXM socket, or some other problem in that area. I doubt that the original 5750 is actually bad since there are very few reported failures of this particular AMD gpu. If you are able to get that working then you will know that you have a good base platform to work with for upgrading to a metal gpu. Good luck with your troubleshooting the 5750 black screen problem. Note also: the 2010 iMac 11,3 is a very good platform for metal gpu and Big Sur using OCLP.

Thanks to davidg5678 for his very detailed posts earlier in this thread for helping me upgrade my 2010 iMac 11,3 to the WX4150/RX460.

Edit: another very likely possibility is the LVDS cable from the mainboard to the monitor is loose or not seated properly.
 
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I recently bought an iMac 27" from Mid 2010 (i5, 12GB RAM, HD5750, 512GB SSD). The seller stated that the GPU was damaged (which was stated by a professional he gave it to). When I power up the iMac just the fans start up but there is no image at all, is this normal for a bad GPU?

My next question is: I wanted to update the iMac to Big Sur. So I'll need a Metal GPU and was thinking about the WX4170 as it seems to be a pretty straight forward option after reading the guide here. Now I still have a question. Is it possible for me to install the WX4170 and get an image straight away or does the GPU need to be flashed first to get any image at all?
I don't have any other macs at home where I could install it to flash it.

This is my first Apple device btw, I tried to read a lot in these forums but not everything is 100% clear to me yet o_O

1. You need to start with a working iMac, not a dead one you have at hand.
2. You need to read post #1 + all the links from post#1 until you fully understand it.
3. You need to draw a plan or checksheet for your specific case.
4. Review your plan/checksheet until you thoroughly understand what to do, what issues may arise, which worst case scenario to expect, etc...

If this is your first Apple device, which by chance is also a dead computer, 99% you will fail with anything you want to do with it, unless your are a genius in electronic/computer repairing business.
 
I recently bought an iMac 27" from Mid 2010 (i5, 12GB RAM, HD5750, 512GB SSD). The seller stated that the GPU was damaged (which was stated by a professional he gave it to). When I power up the iMac just the fans start up but there is no image at all, is this normal for a bad GPU?

My next question is: I wanted to update the iMac to Big Sur. So I'll need a Metal GPU and was thinking about the WX4170 as it seems to be a pretty straight forward option after reading the guide here. Now I still have a question. Is it possible for me to install the WX4170 and get an image straight away or does the GPU need to be flashed first to get any image at all?
I don't have any other macs at home where I could install it to flash it.

This is my first Apple device btw, I tried to read a lot in these forums but not everything is 100% clear to me yet o_O
In order to get an image, the GPU needs to be flashed first, and OpenCore Legacy Patcher needs to be installed on the boot drive. If the GPU is truly the only thing that is wrong with your computer, you should have a reasonably good chance of success. The tricky part is that you won't truly know what's functional and what is damaged when starting out, and this can make diagnosing potential issues much more difficult.

To flash the GPU outside of your iMac, an inexpensive external flashing device can be utilized. This could be used with a PC, Linux, or another Mac computer. Check the first post for more information.

This can be a tricky (and sometimes frustrating process), but it is very rewarding once you get an iMac working again.

My best advice is to read through the first post in its entirety a few more times, and then take notes to help yourself know which instructions apply to your machine.
 
I am hoping someone here can point out where I might have missed something... I don't know if this is due to my WX7100 or if it is OpenCore related (or most likely "human error" on my part :rolleyes:). I am running Big Sur 11.5.2 that was installed using OCLP version 0.2.4.
Probably you need a Recovery CD with SIP and SecureBootModel disabled and verbose enabled to show you what happens during boot. You cannot boot from OpenCore into another OpenCore (i.e first SD, than internal disk)! You can only boot macOS/Linux/UEFI Windows.

Pull all other devices containing an EFI folder from you system (Eject CD and pull SD cards) if you try to boot from the internal EFI and do a PRAM reset on boot to be sure the contents of the former OC are wiped out of the NVRAM.

If the installation works properly it will find the single through OCLP installed EFI folder (never install this yourself if you do not know for 100% which files are needed!!!).

Leave your iMac half open unless you figured out how to handle this problem. I can use my Recovery CD to boot internal and external macOS/Linux installations.

Enable screen sharing and remote access to check how far your black/screen system really got.
 
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Probably you need a Recovery CD with SIP and SecureBootModel disabled and verbose enabled to show you what happens during boot. You cannot boot from OpenCore into another OpenCore (i.e first SD, than internal disk)! You can only boot macOS/Linux/UEFI Windows.

Pull all other devices containing an EFI folder from you system (Eject CD and pull SD cards) if you try to boot from the internal EFI and do a PRAM reset on boot to be sure the contents of the former OC are wiped out of the NVRAM.

If the installation works properly it will find the single through OCLP installed EFI folder (never install this yourself if you do not know for 100% which files are needed!!!).

Leave your iMac half open unless you figured out how to handle this problem. I can use my Recovery CD to boot internal and external macOS/Linux installations.

Enable screen sharing and remote access to check how far your black/screen system really got.
While an OCLP Recovery CD is really a very useful tool, I do think putting OCLP on an SD card for upgraded AMD metal GPU is more versatile for iMac 2009 to 2011. Some of us may even have the DVD drive removed for an additional SSD or other modding. An SD card is small and non-obtrusive when put in the SD slot. Its content can be readily updated. You can also have multiple SD cards prepared for testing before a definite update to a stable version. The OCLP SD card can be removed after booting to access pictures or files on other SD cards if needed with no problem. You just need the OCLP SD card for your next reboot. So, if you don't use your SD slot often, just leave the OCLP SD card inserted and forget about it. Thus, I don't bother to install OCLP to my 3 internal SSDs, each of which is holding a different macOS (Catalina, Big Sur, and Monterey). I just need to update my OCLP SD card once to cater for the 3 different macOS.

Besides, the current AMD GOP vBIOS doesn't support the native Apple BootPicker on pressing the Option key at booting, you will be greeted with a black screen if the EFI partition is corrupted by nature or during os upgrade or an incompatible or buggy nightly build, you won't be able to see nor choose your boot volume upon restart. THat makes troubleshooting very difficult without opening your iMac and disconnecting the HD/SSD.
 
I had an interesting experience with using the recovery CD. As I was preparing to transition from Catalina Loader to OCLP to support upgrading my mid-2011 27 inch iMac (see signature block) to Big Sur, I did a PRAM reset when I shouldn't have (see post #15940). I built the recovery CD with my MacBook Pro and I was able to boot my iMac. However, I was unable to get the machine to boot from any other source after this (USB, SD card, SSD) despite following the instructions to copy the EFI over to the other boot sources or building the EFI directly to the other boot sources using the OpenCore Patcher (TUI version). I could see all the proper files in the EFI folders that were built, but each time I tried to get the machine to boot up from another source other than the recovery CD, all I would get was the black screen (the recovery CD worked every time without any issues).

Ultimately, I opened up the machine and disconnected the SSD and hard drive in order to get it to boot with the OpenCore EFI from the SD card. From there, I executed the upgrade to Big Sur (I wiped my SSD and did a clean install) and everything is working normally using the SD Card.

I would now like to take the step to put the boot EFI onto the internal SSD so I don't need the SD card. I have tried a several more times to build the EFI onto the internal SSD using the OpenCore Patcher and also by mounting copying the EFI folder contents to the EFI folder on the SSD. I have utilized post #1, #15919, #16001, OCLP instructions on Github, and #8,650 on the OpenCore on the MacPro thread to support troubleshooting. Nothing was worked at this point. I have even done several PRAM resets, each of which has required me to open my iMac to disconnect the drives in order to restore the ability to boot from the SD Card. Each time I remove my SD card to try to boot from the internal SSD, all I get is the black screen. When I boot from the SD Card, the boot picker shows me options for the SSD EFI and my Big Sur drive, so it appears that the SSD EFI is definitely there, but for some reason my iMac doesn't see it when booting.

I am hoping someone here can point out where I might have missed something... I don't know if this is due to my WX7100 or if it is OpenCore related (or most likely "human error" on my part :rolleyes:). I am running Big Sur 11.5.2 that was installed using OCLP version 0.2.4.
As far as I know, the EFI folder generated from OCLP is hardware related. One created from MacBook Pro might not work or not be optimized for another different Mac e.g. iMac.

Besides, I prefer to test a new OCLP version on a SD card to see whether it really works instead of directly installing it on the system volume for testing in case it might not work due to bugs.
 
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Besides, the current AMD GOP vBIOS doesn't support the native Apple BootPicker on pressing the Option key at booting, you will be greeted with a black screen if the EFI partition is corrupted by nature or during os upgrade or an incompatible or buggy nightly build, you won't be able to see nor choose your boot volume upon restart. THat makes troubleshooting very difficult without opening your iMac and disconnecting the HD/SSD.
That's the very reason for having a bootable OpenCore CD - for recovering you can always boot from the optical drive by holding the "C" key on boot, without having to open your iMac.
You might have to reset the PRAM before the OpenCore version on the CD works correctly, but after that you should always be able to recover.
 
I recently bought an iMac 27" from Mid 2010 (i5, 12GB RAM, HD5750, 512GB SSD). The seller stated that the GPU was damaged (which was stated by a professional he gave it to). When I power up the iMac just the fans start up but there is no image at all, is this normal for a bad GPU?

My next question is: I wanted to update the iMac to Big Sur. So I'll need a Metal GPU and was thinking about the WX4170 as it seems to be a pretty straight forward option after reading the guide here. Now I still have a question. Is it possible for me to install the WX4170 and get an image straight away or does the GPU need to be flashed first to get any image at all?
I don't have any other macs at home where I could install it to flash it.

This is my first Apple device btw, I tried to read a lot in these forums but not everything is 100% clear to me yet o_O
You should first make sure that your iMac does still work, besides the presumably dead graphics card.
A first indicator would be the typcial Mac boot chime - which you don't mention to appear.
So you should first do a NVRAM/PRAM reset; just search the internet for how to do this.
After that NVRAM/PRAM reset you should hear the boot chime - if not, something makes your Mac crash even before being able to play that chime; you'll have to open your iMac and remove the graphics card in order to see whether that's the cause.
If you hear the boot chime with the graphics card removed (no need to reinstall the display for testing) then you may start to search for a replacement graphics card. Again, you might have to do the NVRAM/PRAM reset after removing the graphics card, in order to get the boot chime.
In case there's still no boot chime then it's up to you whether you want to continue investigating the problem on your own.
 
I have this same iMac and had the HD5750. I followed the posts by davidg5678 and successfully upgraded earlier this year to the same WX4150 that he did. Here is the link: davidg5678 2010 iMac WX4150

Very happy with the WX4150 which is reported as an RX460 4GB on mine. If you take your time and follow the steps carefully you will have a good chance for success with the WX4150, not sure about the 4170 since I have no experience with that gpu. I am running Big Sur 11.5.2 using OCLP 0.2.5 and could not be happier with this now ten year old iMac.

Note about your stock HD5750: this was a solid gpu not known for failures like other AMD gpus of that era. I would suggest investigating getting that gpu working first before ordering any upgrade gpu by opening the iMac and disassembling to the HD5750 MXM module. It is possible the module has become loose or unseated in the MXM socket, or some other problem in that area. I doubt that the original 5750 is actually bad since there are very few reported failures of this particular AMD gpu. If you are able to get that working then you will know that you have a good base platform to work with for upgrading to a metal gpu. Good luck with your troubleshooting the 5750 black screen problem. Note also: the 2010 iMac 11,3 is a very good platform for metal gpu and Big Sur using OCLP.

Thanks to davidg5678 for his very detailed posts earlier in this thread for helping me upgrade my 2010 iMac 11,3 to the WX4150/RX460.

Edit: another very likely possibility is the LVDS cable from the mainboard to the monitor is loose or not seated properly.
Thanks, I'll check out that card with the link too then!
I already checked if the GPU was well seated and also looked at the cable connections for the display, which seemed to be ok too...

1. You need to start with a working iMac, not a dead one you have at hand.
2. You need to read post #1 + all the links from post#1 until you fully understand it.
3. You need to draw a plan or checksheet for your specific case.
4. Review your plan/checksheet until you thoroughly understand what to do, what issues may arise, which worst case scenario to expect, etc...

If this is your first Apple device, which by chance is also a dead computer, 99% you will fail with anything you want to do with it, unless your are a genius in electronic/computer repairing business.
Thank you for your feedback. I did read post #1 multiple times, it is very well written, but I must say for someone with no expierence with Apple devices stuff gets confusing pretty fast haha. Might be a bit of a big project to start with but we'll see, I'm in no hurry.

In order to get an image, the GPU needs to be flashed first, and OpenCore Legacy Patcher needs to be installed on the boot drive. If the GPU is truly the only thing that is wrong with your computer, you should have a reasonably good chance of success. The tricky part is that you won't truly know what's functional and what is damaged when starting out, and this can make diagnosing potential issues much more difficult.

To flash the GPU outside of your iMac, an inexpensive external flashing device can be utilized. This could be used with a PC, Linux, or another Mac computer. Check the first post for more information.

This can be a tricky (and sometimes frustrating process), but it is very rewarding once you get an iMac working again.

My best advice is to read through the first post in its entirety a few more times, and then take notes to help yourself know which instructions apply to your machine.
Ok perfect that is what I needed to know! I'll see how I can manage to do this then.

You should first make sure that your iMac does still work, besides the presumably dead graphics card.
A first indicator would be the typcial Mac boot chime - which you don't mention to appear.
So you should first do a NVRAM/PRAM reset; just search the internet for how to do this.
After that NVRAM/PRAM reset you should hear the boot chime - if not, something makes your Mac crash even before being able to play that chime; you'll have to open your iMac and remove the graphics card in order to see whether that's the cause.
If you hear the boot chime with the graphics card removed (no need to reinstall the display for testing) then you may start to search for a replacement graphics card. Again, you might have to do the NVRAM/PRAM reset after removing the graphics card, in order to get the boot chime.
In case there's still no boot chime then it's up to you whether you want to continue investigating the problem on your own.
No the boot chime did not appear, only fans spinning, that's what I found a bit strange. But thanks for your tips, I'll remove the graphics card during the next days or so, inspect it, do the NVRAM/PRAM reset and see what results I can get with that.

Thanks to all of you for your quick responses! I'll keep you updated on my progress.
 
Probably you need a Recovery CD with SIP and SecureBootModel disabled and verbose enabled to show you what happens during boot. You cannot boot from OpenCore into another OpenCore (i.e first SD, than internal disk)! You can only boot macOS/Linux/UEFI Windows.

Pull all other devices containing an EFI folder from you system (Eject CD and pull SD cards) if you try to boot from the internal EFI and do a PRAM reset on boot to be sure the contents of the former OC are wiped out of the NVRAM.

If the installation works properly it will find the single through OCLP installed EFI folder (never install this yourself if you do not know for 100% which files are needed!!!).

Leave your iMac half open unless you figured out how to handle this problem. I can use my Recovery CD to boot internal and external macOS/Linux installations.

Enable screen sharing and remote access to check how far your black/screen system really got.
@Ausdauersportler - Thanks for the reply. I am pretty sure I tried your suggestion to do a PRAM reset with with the SD card and CD removed, but I will try it again. If that doesn't work, I will try sharing the screen - which was successful to help me work through installing Mojave last year with your help (post #8421) 🙂. I am ashamed I didn't think about trying that again myself... :rolleyes:🤦‍♂️

While an OCLP Recovery CD is really a very useful tool, I do think putting OCLP on an SD card for upgraded AMD metal GPU is more versatile for iMac 2009 to 2011. Some of us may even have the DVD drive removed for an additional SSD or other modding. An SD card is small and non-obtrusive when put in the SD slot. Its content can be readily updated. You can also have multiple SD cards prepared for testing before a definite update to a stable version. The OCLP SD card can be removed after booting to access pictures or files on other SD cards if needed with no problem. You just need the OCLP SD card for your next reboot. So, if you don't use your SD slot often, just leave the OCLP SD card inserted and forget about it. Thus, I don't bother to install OCLP to my 3 internal SSDs, each of which is holding a different macOS (Catalina, Big Sur, and Monterey). I just need to update my OCLP SD card once to cater for the 3 different macOS.

Besides, the current AMD GOP vBIOS doesn't support the native Apple BootPicker on pressing the Option key at booting, you will be greeted with a black screen if the EFI partition is corrupted by nature or during os upgrade or an incompatible or buggy nightly build, you won't be able to see nor choose your boot volume upon restart. THat makes troubleshooting very difficult without opening your iMac and disconnecting the HD/SSD.
Thanks for the feedback. I agree with you that using the SD card slot is not a huge deal. In fact, I have used it for the past year with Catalina Loader on the SD card to support running Mojave on my iMac and I really don't have any complaints. However, I am trying to simplify the boot process and requirements a little bit more for others in my home who have tried to boot without the SD card inserted... :eek::rolleyes::(. If I can't get it to work, I am perfectly happy keeping the SD card installed as I have had it for the past year.

As far as I know, the EFI folder generated from OCLP is hardware related. One created from MacBook Pro might not work or not be optimized for another different Mac e.g. iMac.

Besides, I prefer to test a new OCLP version on a SD card to see whether it really works instead of directly installing it on the system volume for testing in case it might not work due to bugs.
I tried creating the EFI folder (both manually and using the OCLP program) using both my iMac and my MBP and neither worked. This included changing the model in the OpenCore Patcher program (option #4) and overriding the GPU to ensure support for my AMD GPU built into the OC files (Advanced Settings option).

Thank you all for your time and responses. I will report back if I am successful, probably this next weekend.
 
Thank you for your feedback. I did read post #1 multiple times, it is very well written, but I must say for someone with no expierence with Apple devices stuff gets confusing pretty fast haha. Might be a bit of a big project to start with but we'll see, I'm in no hurry.

We all wish that you are lucky and the only dead part in your iMac is the GPU (MXM graphic card).
But maybe you are a little over optimistic about your dead iMac.
I've always been skeptical and hesitate to pay my bloody money for a dead (black screen) iMac. I insists on confirming it in working order before paying, even if I have to bring over an original Apple GPU and assemble it at the seller's place.

Dead GPU is only one issue of those old iMacs.
The previous owner might have attempted to repair/upgrade it, and left some surprises inside, this is the reason it was sold "as is" (i.e "for parts"/"as junk")
Belows are some of the "surprises" of a "blackscreen iMac", assuming that all other parts are still intact and working:

- Broken V-sync cable
- Broken LCD backlight power cable/female jack
- Dead LCD backlight board
- Broken LVDS cable
- Dead LED strips
- Knocked-off/broken components on the logicboard.
- Broken LVDS socket/Bad LCD panel (thin strips on the screen when it displays image)

Except for the last one, all other issues can be repaired at little cost on replacement parts, but they are a nightmare for trouble shooting.

To me, the most value part in a 2009~2011 iMac is its 27" 2K LCD. If I couldn't confirm that it's still lighting and displaying image without any black spots, dark corner, discolored strips, I would only offer a buying price that covers only the aluminium frame and the protection glass, or retreat from the deal.
 
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iMac 2011 21 inch K610M has successfully installed Catalina 15.7.5 with opencore 0.5.9 ,is it possible to
upgrade higher version of opencore ,Graphics acceleration,H.264 not working .
 
iMac 2011 21 inch K610M has successfully installed Catalina 15.7.5 with opencore 0.5.9 ,is it possible to
upgrade higher version of opencore ,Graphics acceleration,H.264 not working .
yes, you can upgrade to higher version of macOS than Catalina with your metal compatible K610 GPU, but you need to change to OCLP 0.2.4 or later. Graphic and H.264 hardware acceleration DO NOT work with nVidia GPUs. Read the 1st post. If you need that acceleration, should change to another low end AMD GPU like WX4130 or 4150. However, depending on your usage, consider a M1 MacMini if you are really into graphics and video editing, instead of investing more on your old iMac.
 
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iMac 2011 21 inch K610M has successfully installed Catalina 15.7.5 with opencore 0.5.9 ,is it possible to
upgrade higher version of opencore ,Graphics acceleration,H.264 not working .
Additionally you need to enable either the VMware flags or to use moderate spoofing to see and load Catalina updates via the Apple Softwareupdate. The weird thing is you can always see und update to Big Sur directly without changing the config.
And yes, H.264 will remain broken with OCLP - check the first post, again!
 
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The graphics on my mid 2011 27" imac​



Old Macs
Let me explain,
The graphics on my mid 2011 27" imac failed. :/
So I want replacement gpu (quadro k610m).
Do I need to flash it to work on High Sierra or a patched mojave or catalina?
 

The graphics on my mid 2011 27" imac​



Old Macs
Let me explain,
The graphics on my mid 2011 27" imac failed. :/
So I want replacement gpu (quadro k610m).
Do I need to flash it to work on High Sierra or a patched mojave or catalina?
Yes, you will have to, otherwise:

  1. The loss of EFI boot screen;
  2. The loss of backlight control;
  3. You can only connect one external monitor to 27" iMacs;
  4. The loss of Target Disk Mode;
  5. The loss of Target Display Mode (TDM); (works only with High Sierra and before)
  6. The loss of running the built-in Apple Hardware Test (AHT);
  7. The loss of temperature sensors on the new GPU. But there is a hardware solution!
 
Yes, you will have to, otherwise:

  1. The loss of EFI boot screen;
  2. The loss of backlight control;
  3. You can only connect one external monitor to 27" iMacs;
  4. The loss of Target Disk Mode;
  5. The loss of Target Display Mode (TDM); (works only with High Sierra and before)
  6. The loss of running the built-in Apple Hardware Test (AHT);
  7. The loss of temperature sensors on the new GPU. But there is a hardware solution!
Let say all I want is to use computer no plug and play except original type of card. Do t care about boot menu or brightness etc etc
 
You’ll have to do that (after all you will have to check to ensure that the card you got is functional)
 
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