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

[BadBiscuit]

Ok will try CH341a method thank you. Also i have black screen without any back lights...

You may find the CH341a won't work with that card. I don't have personal experience with that one, but seem to recall reading the bios chip is not clippable. Regardless you would need to uninstall and remove heatsink. Do some research to confirm for others have posted experience with that card.

 

[xNuGGax]

You may find the CH341a won't work with that card. I don't have personal experience with that one, but seem to recall reading the bios chip is not clippable. Regardless you would need to uninstall and remove heatsink. Do some research to confirm for others have posted experience with that card.

I almost check all information but i don't found any similarities with my situation... i almost made heatsink modification... anyway until someone with similar card will help me with this problem will try make more research. Thank you for support!

 

[Ausdauersportler]

Hi avryone!
I need some support with my 27 iMac 2011 GPU upgrade. I hope you can help make this job done step by step and want let many thanks in advance for supporting.

1. So actually my old GPU is totally dead and i bought replacement nvidia quadro K4100M.
2. I installed new GPU.
3 i received only 2 LEDs on motherboard and black screen. Also starup sound is apears after 30 20 second fans star working in full speed.
4. I have no any macOS installed on my imac have only windows 10.

What should i do now for make this card work properly? Can someone explain me?

You have to flash, clip will unlikely work since the cards has a WSON type chip, so use the Linux method. Everything is described in detail on the very first post of this page, including the usual problem that you will experience a black screen without a proper BIOS (Q2 of the FAQ). This is the normal case.

So just go back and read carefully and plan your actions according to the information given. There is even a short plan provided....

 

[Danwilderspin]

hi all does airplay work for you after the upgrade? if so did you need to do anything to make it?

 

[The_Croupier]

I have the same feature with one K5000M and one K3000M only in iMac Mid 2011 systems. In all other systems these cards are running perfectly.

The same applies to a 880M of a friend living nearby which I had for a short time to flash the BIOS. It worked only in the Late 2009 test system I had, not in the 2011 systems showing exactly the same problem.

The main problem: It does not happen with all of these cards.

So I cannot help finding a solution but if I were in your shoes I would give up this card for the use in an 2011 system. It is not worth the trouble and time you already wasted into this project.

On the other hand it would be nice to find the root cause, but I am sure it is not the physics or the card installation, it is likely the iMac 2011 firmware which does not like some of the AMD cards, too.

Thank you so much for sharing your previous experience with me, you are absolutely correct. I just tried the card in a 2010 and it works!!!!

Will test it in my sons 2009 on the weekend, ultimately the card is for him so he could play RUST on his iMac 🙄 I was going to upgrade him to a 2011 and give the 2009 to mum (hence all the wasted time mucking around on the 2011's) but heck if it works in his 09 thats where it will stay, dont really want to give up my 2010 as I have had it since release and it has never let me down.

Your right It would be great if we could work out what causes this compatibility issue between different machines, seeing how it pretty much can brick your EFI Bios firmware I think your correct in that assumption.
I had a heck of a time getting the 2011 to boot properly again, when PRAM resets were not working I had to remove all power, RAM and battery and let it sit for a while, frustrating to say the least but no permanent damage.

Added data to the performance spreadsheets.

 

[Ausdauersportler]

Saving the firmware using romtool and editing it using UEFItool is not that complicated. Flashing back needs the CH341A /or possible the efiflash tool available with OpenCore may work, too.

The problem is:

I have no clue where to search for the code which breaks the MXM compatibility on 2011 systems. There are some projects in the pipe to replace the WiFi part with one from 2014/15 iMacs to get internet recovery over WiFi back if you use upgraded BCM94360x cards. This code has been found.

Playing back the original firmware restores full functionality on the board. So I am not so afraid of breaking things here. Pulling out the system board to change a GPU itself is more dangerous, if you ask me...

 

[m0bil]

Saving the firmware using romtool and editing it using UEFItool is not that complicated. Flashing back needs the CH341A /or possible the efiflash tool available with OpenCore may work, too.

The problem is:

I have no clue where to search for the code which breaks the MXM compatibility on 2011 systems. There are some projects in the pipe to replace the WiFi part with one from 2014/15 iMacs to get internet recovery over WiFi back if you use upgraded BCM94360x cards. This code has been found.

Playing back the original firmware restores full functionality on the board. So I am not so afraid of breaking things here. Pulling out the system board to change a GPU itself is more dangerous, if you ask me...

Have you found any case where a card that does not work on a 2011 iMac but works on another apparently identical 2011 iMac ?

I'm asking because the friend I bought my 780M from had the very same symptoms as others on this thread with it:
card works fine on windows laptop, but when mounted on his 27'' 2011 iMac, boots without display attached, but after flashing it with linux tool, it no longer boots, just black screen and chime loop.

He lends it to me and I tested on my same board-id and display-id iMac, and to my surprise it works...

It may be a bad install on his iMac, but he tried several times (remounting, three pram resets without card, etc.) and he's very skilled...

Only thing I see different between our machines may be memory and smc firmware version ...

 

[MrZupp]

Have you found any case where a card that does not work on a 2011 iMac but works on another apparently identical 2011 iMac ?

I'm asking because the friend I bought my 780M from had the very same symptoms as others on this thread with it:
card works fine on windows laptop, but when mounted on his 27'' 2011 iMac, boots without display attached, but after flashing it with linux tool, it no longer boots, just black screen and chime loop.

He lends it to me and I tested on my same board-id and display-id iMac, and to my surprise it works...

It may be a bad install on his iMac, but he tried several times (remounting, three pram resets without card, etc.) and he's very skilled...

Only thing I see different between our machines may be memory and smc firmware version ...

I have the same exact issue as you and @dream_catcher and I did exactly what you did to try and fix it, but i've had no luck

 

[Ausdauersportler]

Have you found any case where a card that does not work on a 2011 iMac but works on another apparently identical 2011 iMac ?

I'm asking because the friend I bought my 780M from had the very same symptoms as others on this thread with it:
card works fine on windows laptop, but when mounted on his 27'' 2011 iMac, boots without display attached, but after flashing it with linux tool, it no longer boots, just black screen and chime loop.

He lends it to me and I tested on my same board-id and display-id iMac, and to my surprise it works...

It may be a bad install on his iMac, but he tried several times (remounting, three pram resets without card, etc.) and he's very skilled...

Only thing I see different between our machines may be memory and smc firmware version ...

I have seen this with K3000M and once with a K3100M and one K41000M card not willing to work in a series of iMac 2011 27 systems but after doing testing and changing I found at last a single working combination!

Unfortunately it was no my system and I forgot to mark the firmware dump - so I do not know where so search now for a difference.

Normally I try hard to upgrade all iMacs I touch to the latest firmware/SMC release.

 

[xbox3605]

hi, can someone tell me why it's freezing when i try to boot from open core 0.6.6?

 

[MrZupp]

I have seen this with K3000M and once with a K3100M and one K41000M card not willing to work in a series of iMac 2011 27 systems but after doing testing and changing I found at last a single working combination!

Unfortunately it was no my system and I forgot to mark the firmware dump - so I do not know where so search now for a difference.

Normally I try hard to upgrade all iMacs I touch to the latest firmware/SMC release.

So it's all just a lottery?

 

[dream_catcher]

I have seen this with K3000M and once with a K3100M and one K41000M card not willing to work in a series of iMac 2011 27 systems but after doing testing and changing I found at last a single working combination!

Unfortunately it was no my system and I forgot to mark the firmware dump - so I do not know where so search now for a difference.

Normally I try hard to upgrade all iMacs I touch to the latest firmware/SMC release.

Thats so weird, because the first time i swap the old amd to this new Nvidia K3100M it booted all fine and it worked good. After i turned on wifi it went black till this day.
So it must be something related software.

 

[wilma127]

...some steps further: I soldered out the chips and put it directly onto the programmer. All voltages are correct according to the datasheet EXCEPT Pin7, which should be 3,3V is at 5V (4,3V in the circuitry). But the chip is readable. while programming Pin7 voltage should be low (IS low while reading), but is 2,75V. I now short circuited this Pin while programming to ground, so that "low" is really low==0V. Still the chip refuses to be written.

I now will test a new chip, which is on it's way.

...some days later I have to report bad things. This is what happened:

• the new EEPROM(s) Pm25LD020 came and I flashed it with the 780M_BR3.rom
• the flash process and verifying worked fine immediatly without any changes to my setup with the CH341A, so I assume the original EEPROM is most likely defective.
• soldered the new EEPROM back in and put the GTX780m back into the iMac as before, applying new K5 where needed
• turned on the iMac and got a black screen with several repeatings.
• connected a secondary monitor, tried again and got a white bootscreen. Windows failed to boot
• tried again and chose to boot MacOS high sierra, which booted fine. The card was recognized with the Nikey VBIOS, but only the secondary display was detected, not the internal.
• rebooted several times and noticed green artefacts (blocks) over the whole screen randomly.
• did a NVRAM reset, which worked fine but didn't resolve the black screen issue (changed none of the symptoms)
• switched to another internal display, which I had handy - no luck
• gave the card a last chance and baked it in the preheated oven for 9mins. @200degrees C
• put all back together
• the green artefacts are completely gone, but
  • still no internal screen,
  • no internal screen detection by high sierra
  • no windows boot
  • the secondary screen now repeatedly and randomly blanks out (the system freezes meanwhile) and comes back again

I will now call this a story and look for another GPU.

Any comments?

 

[MrZupp]

Thats so weird, because the first time i swap the old amd to this new Nvidia K3100M it booted all fine and it worked good. After i turned on wifi it went black till this day.
So it must be something related software.

That's weird, my AMD card is still working but sometimes the imac shuts down on itself, so I think that it may be because of the AMD card.

 

[jay508]

They only have one of those GTX 765M left, so i'm still on the hunt for a other card. I just had a look at the Quadro' and found a K1000M for a descent price. Can someone tel me this card works? It has a GK107GL chip. Where does GL stand for? Also found an K500M, containing an GK107, same as the K2000M. Would this one work?

I had a look at the wiki page: https://en.wikipedia.org/wiki/Nvidia_Quadro The K500M has a MXM-A (3.0) interface and the K2000M a PCI-E 3.0x16 Why is that?

And did someone tried the XServe GPU P815 in the iMac? This one: https://www.ebay.de/itm/Apple-631-0...532071&hash=item2619cd4361:g:7j4AAOSwC71crJ96 This is an GT120

Hi, I have three graphics cards of k500m.k510m and gtx540m. There is no suitable vbios for iMac. The provider of the original vbios of the three specifications can help with the test.

 

[jay508]

Hi, I have three graphics cards of k500m.k510m and gtx540m. There is no suitable vbios for iMac. The provider of the original vbios of the three specifications can help with the test.

Friends who are interested in participating, can help test the vbios that iMac can use

 

[Ausdauersportler]

...some days later I have to report bad things. This is what happened:

• the new EEPROM(s) Pm25LD020 came and I flashed it with the 780M_BR3.rom
• the flash process and verifying worked fine immediatly without any changes to my setup with the CH341A, so I assume the original EEPROM is most likely defective.
• soldered the new EEPROM back in and put the GTX780m back into the iMac as before, applying new K5 where needed
• turned on the iMac and got a black screen with several repeatings.
• connected a secondary monitor, tried again and got a white bootscreen. Windows failed to boot
• tried again and chose to boot MacOS high sierra, which booted fine. The card was recognized with the Nikey VBIOS, but only the secondary display was detected, not the internal.
• rebooted several times and noticed green artefacts (blocks) over the whole screen randomly.
• did a NVRAM reset, which worked fine but didn't resolve the black screen issue (changed none of the symptoms)
• switched to another internal display, which I had handy - no luck
• gave the card a last chance and baked it in the preheated oven for 9mins. @200degrees C
• put all back together
• the green artefacts are completely gone, but
  • still no internal screen,
  • no internal screen detection by high sierra
  • no windows boot
  • the secondary screen now repeatedly and randomly blanks out (the system freezes meanwhile) and comes back again

I will now call this a story and look for another GPU.

Any comments?

So you have a black screen on boot?

Tried reading the first post or searching the thread?

 

[kmare]

It looks like the video memory is over-heating, try turning your ODD fan up.

If that doesn't fix it try flashing this patched bios with lower memory clocks,

it will also enable brightness control on 765M & 770M with the OpenCore loader!

This hybrid 780M bios doesn't need OpenCore, it just fixes the Boot Camp problem.

Enjoy!

@Santa's Little Helper thank you! I had issues with UEFI boot of windows 10 and 780M (no video on nvidia driver install). This re-enabled legacy BIOS boot for bootcamp; and I have dual boot for Windows 10 and Catalina working PERFECTLY!

 

[Ausdauersportler]

hi, can someone tell me why it's freezing when i try to boot from open core 0.6.6?

Hi, can someone tell us which system, which GPU, which macOS?

 

[Umarx]

Yes, that's all completely normal - it's just that you don't understand yet how Catalina Loader and/or OpenCore work.
The only thing that matters now is that your Mac automatically launches OpenCore when powering it on, without holding the option key.
In case it does so, that's all you need in order to test whether your WX4130 is actually working.

Thanks a lot for the encouragement.

I have installed the WX4130 and booted the iMac, I came to boot choice screen and selected internal drive but it breaks the startup towards end and screen goes black (video attached). If I choose to boot in CL I come to the attached screen. No idea what to do with my limited knowledge.

Thanks for all your guidance.

 

[globetribe]

Thanks a lot for the encouragement.

I have installed the WX4130 and booted the iMac, I came to boot choice screen and selected internal drive but it breaks the startup towards end and screen goes black (video attached). If I choose to boot in CL I come to the attached screen. No idea what to do with my limited knowledge.

Thanks for all your guidance.

View attachment 1748056

Are you able to boot on High Sierra without Catalina loader and second screen ?

 

[arkade]

Maybe I am going crazy but I can't for the life of me find the latest vBIOS downloads links. I'm looking for GTX 780M. Thanks.

 

[The_Croupier]

Maybe I am going crazy but I can't for the life of me find the latest vBIOS downloads links. I'm looking for GTX 780M. Thanks.

Page 1 / table of working NVIDIA cards / GTX780M Link
Post in thread '2011 iMac Graphics Card Upgrade' https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614/post-28723899

 

[arkade]

Page 1 / table of working NVIDIA cards / GTX780M Link
Post in thread '2011 iMac Graphics Card Upgrade' https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614/post-28723899

Ha! I am sure I clicked that a number of times. Maybe I wasn't signed in! I presume BR3 is more up-to-date than BR2, but how come there are both to choose from?

 

[Ausdauersportler]

Ha! I am sure I clicked that a number of times. Maybe I wasn't signed in! I presume BR3 is more up-to-date than BR2, but how come there are both to choose from?

Read the post with the BIOS.