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

[dast]

After months of reading this thread I finally had to register in order to thank @nikey22 @xanderon @Ausdauersportler and all others who have contributed to all the information here.

I had purchased a second hand iMac 27 Mid 2011 about 2 years ago. The original graphic card had already been replaced in 2016, but the replacement 6970 1GB was dying. Thankfully to this thread and all the detailed information, I managed to decide for a K3100M, as well as all necessary tools to dismantle the mac (and K5 Pro).

Spend quite some time to disassemble, grind the heatsink, reassemble, flash, ...
Took my time, following all the explanations of the first post.
Finally I can say I now have a booting iMac with a working GPU !!!

Still need to perform the final assembly, as I now want to put an SSD in for faster booting (etc), and also perform the necessary tests.
Again, THANK YOU to everyone to have made this a thrilling but successful GPU replacement.

EDIT:

 

[gnommak]

Installed K3100M, have changed the BIOS chip as one on card was too small, have flashed with the new VBIOS, clean HS install. System now shows the bootloader screen and chimes but after the progress bar I just get a white screen.

Memory on my K3100M is H5GC2H24BFR chips, which is a lower bandwidth and voltage chip than H5GQ2H24BFR

I have same situation. Word by word. Even memory model is the same.
I have installed my K3100M in iMac 27 2011. It booted in to Linux terminal. For first I didn't expect that there will be any video signal. So I just flash the card directly on iMac and rebooted. Got Boot screen. Selected 10.13.5 install USB. Progress bar appeared and after ~ 1 minute I got white like milk screen. It's quite interesting because we both have same symptoms and it's not screen gpu glitches.

I did some investigation. My video card native BIOS is 80.04.E8.00.21 closest brother is 80.04.F1.00.12. Both those cards have H5GC2H24BFR chips. First BIOS is from Z series HP notebooks and second from HPE ProLiant servers. Only difference in functionality is that first support 1 built in display and 1 external. And second 4 external displays.
Also I found that cards with BIOS 80.04.CD.00.0A use memory chips H5GQ2H24AFR (see on attached picture). Exactly that BIOS that mentioned in nikey22 post. And possibly with H5GQ2H24AFR memory chips.

So I can assume that strap resistors should exist on board because we already have memory with different bandwidth.
I have no idea if this can help with our white screen.

Look to ur memory VRAM name, if you see H5GQ2H24BFR (BFR) bios downloaded its not supported to ur ram!
you need change strap resistor upper side ur card from 24,5Khom to 15,4Khom
this solution for K3100M with H5GQ2H24BFR memory.

I looking on card for about an 2 hours. But can't find those resistors. Do you hame service board view? Or can point where on board those resistors should be?

 

[Timmyt1000]

Hello Everyone,


I recently picked up a mid 2011 21.5 inch it is spec'd in my signature below but it is the base i5 model with some extra ram and an ssd upgrade. I am looking to upgrade the GPU so I can use the Dosdude patcher to get on Catalina. I am looking to do the least amount of modifications possible. IE not interested in modifing the heatsink and would prefer to not have to do all the flashing and such at this time. I was looking over the tables listed on page 1 and noticed that some of the GPU's have boot screen listed natively. it seems my best option for my 21.5 inch is the Quadro K2100M as it is listed as natively having a boot screen, it can be modified to have brightness control, does not require modification to the heatsink, and works on the 21.5 inch. So I guess my real question is if I am ok not having brightness control will i be able to disable the imac and swap this in and use my imac or am i going to have to add drivers or something else i seem to have overlooked in all the info provided and is there a better option that requires less modifiations even if the card costs more to purchase.

Basically I have seen some stuff online infer that some of these GPU's can be plug in and used even without boot screen or brightness control. I am just not sure which ones.

Thanks for the help upfront.

 

[Pacific1972]

Thank you for ur answers , the problem now is that i don't know how to use it , i'm a novice in this " world " and i don't know if i'll be able to do this ... i'm really unlucky 😩

To use CH341A Programmer, try out this website (it's for cars, but
you can find CH341A.EXE there). Perhaps you must look for Serialport
emulation also - CH341SER.ZIP.

https://www.car-auto-repair.com/newest-ch341a-usb-programmer-software-free-download/

All runs under Windows and it's much faster and more easy than handle
with other methods...


https://www.car-auto-repair.com/guidehow-to-use-ch341a-usb-programmer/

If connect to the BIOS chip, press "DETECT" and the program must identify a known BIOS chip,
otherwise no action is possible - look at the clamp and connect the clamp exactly - there might be a
red LED glowing on the stick and a yellow LED for read / write action.

If you want to save the original BIOS, then press the icon "Read" and "Save" (HP, lenovo ...) but
if unnecessary for you, read the original BIOS (if there is a BIOS on it) and "Erase" it.

Press "Blank" for checking if the MXIC BIOS Chip is empty !

Then load the selected BIOS.ROM for your card from this Thread #page1.

If selected BIOS.ROM loaded in CH341A Programmer, you can push "Write". After the writing
process you can select the icon "Verify" - if flash the card correctly, the program opens a window
with "CHIP AND BUFFER SAME" !

It's more simple than reading pages of content for NVflash attributes for WIN or Linux or make
a network connection / SSH or some other **** where most users have no experience with...

Please read my last post also with picture how to connect the MXIC BIOS Chip (SOP8) !!!

 

[Ausdauersportler]

Hello Everyone,


I recently picked up a mid 2011 21.5 inch it is spec'd in my signature below but it is the base i5 model with some extra ram and an ssd upgrade. I am looking to upgrade the GPU so I can use the Dosdude patcher to get on Catalina. I am looking to do the least amount of modifications possible. IE not interested in modifing the heatsink and would prefer to not have to do all the flashing and such at this time. I was looking over the tables listed on page 1 and noticed that some of the GPU's have boot screen listed natively. it seems my best option for my 21.5 inch is the Quadro K2100M as it is listed as natively having a boot screen, it can be modified to have brightness control, does not require modification to the heatsink, and works on the 21.5 inch. So I guess my real question is if I am ok not having brightness control will i be able to disable the imac and swap this in and use my imac or am i going to have to add drivers or something else i seem to have overlooked in all the info provided and is there a better option that requires less modifiations even if the card costs more to purchase.

Thanks for the help upfront.

Yes, you missed entirely the OpenCore story, which helps you getting back the native brightness control. I will not repeat here the first post of this thread and let your read through it yourself.

 

[Timmyt1000]

I guess I am missing something here but are some of these GPU's able to be used with out flashing them even if i dont have a boot screen or brightness control

 

[Schprecher]

I have same situation. Word by word. Even memory model is the same.
I have installed my K3100M in iMac 27 2011. It booted in to Linux terminal. For first I didn't expect that there will be any video signal. So I just flash the card directly on iMac and rebooted. Got Boot screen. Selected 10.13.5 install USB. Progress bar appeared and after ~ 1 minute I got white like milk screen. It's quite interesting because we both have same symptoms and it's not screen gpu glitches.

I did some investigation. My video card native BIOS is 80.04.E8.00.21 closest brother is 80.04.F1.00.12. Both those cards have H5GC2H24BFR chips. First BIOS is from Z series HP notebooks and second from HPE ProLiant servers. Only difference in functionality is that first support 1 built in display and 1 external. And second 4 external displays.
Also I found that cards with BIOS 80.04.CD.00.0A use memory chips H5GQ2H24AFR (see on attached picture). Exactly that BIOS that mentioned in nikey22 post. And possibly with H5GQ2H24AFR memory chips.

So I can assume that strap resistors should exist on board because we already have memory with different bandwidth.
I have no idea if this can help with our white screen.

I looking on card for about an 2 hours. But can't find those resistors. Do you hame service board view? Or can point where on board those resistors should be?

look i made solution for u

 

[Ausdauersportler]

I guess I am missing something here but are some of these GPU's able to be used with out flashing them even if i dont have a boot screen or brightness control

Unlikely, some Dell cards run OOB, but with all the seven problems. I do not want to waste our both times with repeating the complete first post. Read through it again and if it is so overwhelming make some notes and a plan for the complete story.

 

[Pacific1972]

look i made solution for u

😆 😆 😆 👍 👍 👍

Hopefully everybody can change this with a 10$ Mini soldering iron !

 

[gnommak]

look i made solution for u

Thx!
I will check this solution this weekend.
And will post the result.

 

[MacBurger31]

so guys, I have a little gift for you to give back after such an incredible thread
hope you like it, the headaches to get it running were immens for me as a newb.

I couldn't stand it to use fckin windows to flash the cards and so I prepared this ~350mb drive

I created a Linux Live USB (based on grml.org) Thumb Drive with nvflash_linux and Nicks Bioses preloaded. and its booting by itself so you can work blind with a new unpatched nvidia card plugged in. Also, its starting a ssh daemon and using DHCP to get an IP so you can remote login

Steps

Download
14 days left to download, uploaded here: https://www.mediafire.com/file/cztz4xqj2sru9gj/2011_imac_usb.zip/file

mirror by NOTNICE, thnx: https://cloud.notnlce.com/index.php/s/xkJP34GD6a9WziE/download


Prepare USB Drive or SD Card
so, you take a small usb thumb drive, partition it with disk utility on a Mac: GPT + FAT32
and just unzip the files structure onto the drive, no dd or etcher or something. just copy paste it. folder structure see attached screenshot. (you can remove the .roms I downloaded and download itself if you want to be sure about the correct file size. I did not verify them at all. use/flash at your own risk please)

Test & Try
test your thumb drive with a more or less working GPU/ external Screen or just have faith in me

Swap Hardware
swap your GPU to NVIDIA and (!) disconnect every SSD/HDD, makes it easier to boot blindly from one USB or SD Card, connect the ETH Cable (!)

Find IP
let the iMac boot, everything is black, the boot loader is waiting 20s before booting, so give the whole process 1min time, then head over to your Router Page and find the right IP that the iMac got through DHCP

SSH to the iMac
now fire up your terminal on a Win/Mac/Linux Machine of your choice and ssh to your iMac with
ssh root@YOURIP
Password: flash
Confirm the ssh id with yes and you should be in your iMac

Working Directory
cd /lib/live/mount/medium/flash

read the RADME in there… I will enjoy my brand new k2000m in my 27" 2011 iMac with Catalina 10.15.3
… and because this is so easy, I rebuild it to a K1100M and flashed that also

(someone could write some fancy scripts but I thought its saver that everyone is doing it command by command and don't stop thinking and trusting some scripts)

Hi guys,

I recently bought a GTX780M to replace my baked 6970M , But with the 1000's of posts here I'm not sure how to proceed. I got the SSH thing up and going, but any steps needed afterwards?
I'm reading native brightness control and bootscreen etc on the 780, yet another post says I'd need opencore and replacing a few kexts to get that up and going.
And anyone have this card up and running with a second display active on thunderbolt in Catalina?
I Have Catalina running on another SSD with the 6970M but the secondary display does not go on.

 

[gnommak]

Hopefully everybody can change this with a 10$ Mini soldering iron !

Yeh it looks complicated, but I have friend that fixing iPhones for last 6 years. He should handle this in 5 minutes

 

[Ri7]

Insulting the BIOS maker and seeking for a step by step guide within minutes - how bad was the education you got? It is people like YOU driving people like me out of this project.

At least you serve as an interesting example of another opportunistic human being - something we possibly need once in a while. Either you leave this thread or you start to be thankful and more polite for all the free work others did for your.

To all others:

There is always the possibility to ignore posts of certain user completely - just move the mouse pointer over the name of the user and press ignore! I did this for this user here here after his third identical post begging for a K3000M BIOS for free, of course.

Perfect!

I really cannot agree MORE!

All this effort have been made, helping too many people, with passion and nothing but hours spent in front of macs...

People needs to learn how to be thankful, but generation "fast food" is slowly killing this...

I take this opportunity to thank you all again, now I have 2 iMacs fully upgraded (K2100m and K4100m), with no problems at all and the ONLY thing I needed to do was READ the post #1...lol

 

[ZenSurfeur]

I used the 1.29 version

 

[ZenSurfeur]

To use CH341A Programmer, try out this website (it's for cars, but
you can find CH341A.EXE there). Perhaps you must look for Serialport
emulation also - CH341SER.ZIP.

https://www.car-auto-repair.com/newest-ch341a-usb-programmer-software-free-download/

View attachment 1685316

All runs under Windows and it's much faster and more easy than handle
with other methods...


https://www.car-auto-repair.com/guidehow-to-use-ch341a-usb-programmer/


View attachment 1685317

If connect to the BIOS chip, press "DETECT" and the program must identify a known BIOS chip,
otherwise no action is possible - look at the clamp and connect the clamp exactly - there might be a
red LED glowing on the stick.

If you want to save the original BIOS, then press the icon "Read" and "Save" (HP, lenovo ...) but
if unnecessary for you, read the original BIOS (if there is a BIOS on it) and "Erase" it.

Press "Blank" for checking if the MXIC BIOS Chip is empty !

Then load the selected BIOS.ROM for your card from this Thread #page1.

If selected BIOS.ROM loaded in CH341A Programmer, you can push "Write". After the writing
process you can select the icon "Verify" - if flash the card correctly, the program opens a window
with "CHIP AND BUFFER SAME" !

It's more simple than reading pages of content for NVflash attributes for WIN or Linux or make
a network connection / SSH or some other **** where most users have no experience with...

I used the 1.29 version under windows 7

 

[MyM]

I have same situation. Word by word. Even memory model is the same.
I have installed my K3100M in iMac 27 2011. It booted in to Linux terminal. For first I didn't expect that there will be any video signal. So I just flash the card directly on iMac and rebooted. Got Boot screen. Selected 10.13.5 install USB. Progress bar appeared and after ~ 1 minute I got white like milk screen. It's quite interesting because we both have same symptoms and it's not screen gpu glitches.

I did some investigation. My video card native BIOS is 80.04.E8.00.21 closest brother is 80.04.F1.00.12. Both those cards have H5GC2H24BFR chips. First BIOS is from Z series HP notebooks and second from HPE ProLiant servers. Only difference in functionality is that first support 1 built in display and 1 external. And second 4 external displays.
Also I found that cards with BIOS 80.04.CD.00.0A use memory chips H5GQ2H24AFR (see on attached picture). Exactly that BIOS that mentioned in nikey22 post. And possibly with H5GQ2H24AFR memory chips.

So I can assume that strap resistors should exist on board because we already have memory with different bandwidth.
I have no idea if this can help with our white screen.

I looking on card for about an 2 hours. But can't find those resistors. Do you hame service board view? Or can point where on board those resistors should be?

My board came with 80.04.E8.00.1C as a BIOS version, only difference I can see is that mine is 699-52053-0501-210 H part number to your F revision.

Will be interested to see if resistor makes any difference to yours.

 

[deniss1711]

For flashing VBIOS IC of my Quadro K3000M and some other mainboard BIOSes the cost effective xgecu tl866ii plus programmer also worked well (at least in Win10). Can also be bought with many adapters for low cost (~80€/$) and has good chip support Supported ICs. GUI for this programmer is usable. WSON8 package can be soldered on SOIC8 adapter (PCB in my kit not testsocket) if a WSON adapter is not available, but recommend checking for shorted pins against thermal pad of WSON8 package before inserting the adapter in ZIF socket of programmer in this case.

Will also give the strapping resistor mod a try, and report what happens on my card.

 

[Zorrogarcia]

To use CH341A Programmer, try out this website (it's for cars, but
you can find CH341A.EXE there). Perhaps you must look for Serialport
emulation also - CH341SER.ZIP.

https://www.car-auto-repair.com/newest-ch341a-usb-programmer-software-free-download/

View attachment 1685316

All runs under Windows and it's much faster and more easy than handle
with other methods...


https://www.car-auto-repair.com/guidehow-to-use-ch341a-usb-programmer/


View attachment 1685317

If connect to the BIOS chip, press "DETECT" and the program must identify a known BIOS chip,
otherwise no action is possible - look at the clamp and connect the clamp exactly - there might be a
red LED glowing on the stick.

If you want to save the original BIOS, then press the icon "Read" and "Save" (HP, lenovo ...) but
if unnecessary for you, read the original BIOS (if there is a BIOS on it) and "Erase" it.

Press "Blank" for checking if the MXIC BIOS Chip is empty !

Then load the selected BIOS.ROM for your card from this Thread #page1.

If selected BIOS.ROM loaded in CH341A Programmer, you can push "Write". After the writing
process you can select the icon "Verify" - if flash the card correctly, the program opens a window
with "CHIP AND BUFFER SAME" !

It's more simple than reading pages of content for NVflash attributes for WIN or Linux or make
a network connection / SSH or some other **** where most users have no experience with...

thank u so much, it's really useful! one question, can u explain me what means (technically talking) "Some BIOS chips (e.g. win-bond type) cannot be flashed easily in this way, especially the nVidia Quadra Kxxxx series GPU" as @KennyW has said ?
i've read about lot of people with issues flashing the winbond 25X20CLNIG chip😖 ( maybe is that what Kenny wanted to say to me)

i'm really sorry for being a burden, but that's really new for me 😊🥶

 

[KennyW]

thank u so much, it's really useful! one question, can u explain me what means (technically talking) "Some BIOS chips (e.g. win-bond type) cannot be flashed easily in this way, especially the nVidia Quadra Kxxxx series GPU" as @KennyW has said ?
i've read about lot of people with issues flashing the winbond 25X20CLNIG chip😖 ( maybe is that what Kenny wanted to say to me)

i'm really sorry for being a burden, but that's really new for me 😊🥶

I only have experience with the other slimmer SOP8 chips with clips in AMD cards.

The difficulty with winbond or 8-WSON chip (mostly in nVidia cards) is that they are fatter (broader) and much more difficult to be clipped with little legs exposed for contact in their surface mount. There is also less adjacent free room for manipulation of your blunt clip ends for secure fixation to the chip due to its wider size and close-by components which may hinder your clip application. It is said to be also less forgiving to bad flashing if poor contact. Hence, it is often suggested to better flash the nVidia card in situ in your iMac or Windows PC.

Perhaps those who have done so may share their personal experience in clipping winbond chips.

 

[motorm3]

Strange issue on my imac mid 2011 27 quadro k3100m after I installed big sur from micropatcher when i first boot in screen looks like it has clouds in the the colours if I play a video on you tube back ground looks cloudy something similar to slow Internet video. But if I put screen to sleep and out of it everything is back to normal but next boot up same problem. I install catalina back again because there everything was good but now same as in big sur does anyone have any idea what has happened.

 

[Nguyen Duc Hieu]

I really don't understand the necessity to use the CH341a clipping method when you already have another windows PC.
Just use this PCIe 1x to MXM adapter and plug the card to a blank PCIe slot in the PC.
You can also check whether the card is recognized in Windows.
From there, it's just 2 command to read the original vBIOS rom and flash the cooked vBIOS rom to the card.

PCI E to MXM3.0 Graphics Card PCI Express X1 to MXM 3.0 Raiser Riser Card Adapter Converter Board with LED for BTC Miner Mining|Add On Cards| - AliExpress

Cheap Add On Cards, Buy Quality Computer & Office Directly from China Suppliers:PCI E to MXM3.0 Graphics Card PCI Express X1 to MXM 3.0 Raiser Riser Card Adapter Converter Board with LED for BTC Miner Mining Enjoy ✓Free Shipping Worldwide! ✓Limited Time Sale ✓Easy Return.

www.aliexpress.com

I made myself the mistake of buying an extra HP USDT to use its MXM slot. But it costs only 50$ and serves as a contingency plan (I didn't know if my WX4150 4GB would be recognized and work at all in the iMac).

 

[KennyW]

Strange issue on my imac mid 2011 27 quadro k3100m after I installed big sur from micropatcher when i first boot in screen looks like it has clouds in the the colours if I play a video on you tube back ground looks cloudy something similar to slow Internet video. But if I put screen to sleep and out of it everything is back to normal but next boot up same problem. I install catalina back again because there everything was good but now same as in big sur does anyone have any idea what has happened.

This color dithering issue has been discussed here though not highlighted in the first post.
It is related to the low bit depth (? 8 or 16) on first activation of the GPU in OSX upon cold start or restart.
With sleeping and rewakening, the OSX graphic drivers will take over into full effect (24 bits) in eliminating that issue.

Have you read the post a few pages back whereby some users made a small application for loading as startup item to address this problem? Again NO easy fix. Wait for developers work on the vBIOS if any. You have to accept that limitation at the time being.

Maybe some kind soul can go through the 400+ pages of information and adds a Q&A session in 1st page on the problems raised and whether solutions are there ... but it is a daunting task 😔
I personally also miss some important info of interest spreading among the 10000+ posts

 

[velvet_man]

Can someone please tell me what I'm doing wrong with the OpenCore install?

I downloaded Catalina Loader dmg and the 0.6.3 zip file. I managed to restore the Catalina Loader DMG to an SD card using SuperDuper (Disk Utility wouldn't even attempt to restore the DMG because it said it had no boot tables or something, and Balena Etcher gave the same errors but attempted to restore it anyway but failed).

Anyway, SuperDuper restored the DMG to the SD card, I copied the EFI folder from the zip over to it, and it shows up in System Preferences. But, whenever I try to select it as the boot drive, it comes up with an error message and won't do it.

This is the error message: "You can’t change the startup disk to the selected disk. Running bless to place boot files failed."

I've searched this thread but couldn't find anything about this error.

 

[BadBiscuit]

I really don't understand the necessity to use the CH341a clipping method when you already have another windows PC.
Just use this PCIe 1x to MXM adapter and plug the card to a blank PCIe slot in the PC.
You can also check whether the card is recognized in Windows.
From there, it's just 2 command to read the original vBIOS rom and flash the cooked vBIOS rom to the card.

PCI E to MXM3.0 Graphics Card PCI Express X1 to MXM 3.0 Raiser Riser Card Adapter Converter Board with LED for BTC Miner Mining|Add On Cards| - AliExpress

Cheap Add On Cards, Buy Quality Computer & Office Directly from China Suppliers:PCI E to MXM3.0 Graphics Card PCI Express X1 to MXM 3.0 Raiser Riser Card Adapter Converter Board with LED for BTC Miner Mining Enjoy ✓Free Shipping Worldwide! ✓Limited Time Sale ✓Easy Return.

www.aliexpress.com

I made myself the mistake of buying an extra HP USDT to use its MXM slot. But it costs only 50$ and serves as a contingency plan (I didn't know if my WX4150 4GB would be recognized and work at all in the iMac).

Good point, though the CH341A only requires a free USB port (i.e. laptop) and they are more easily obtained. I had been wondered if these “PCI-E to MXM3.0” adapters would work, so thanks for answering that. Do you plug it directly to the motherboard’s PCI-E 1X slot, or use a riser with “stable power supply” as your link recommends? If so which riser do you use/recommend? Perhaps something like this?

PCI Express Adapter PCI-E 1X to 16X Slot Riser Card Extender USB 3.0 Cable 4Pin Dual 6pin Power Supply for BTC Miner Mining

 

[Schprecher]

For flashing VBIOS IC of my Quadro K3000M and some other mainboard BIOSes the cost effective xgecu tl866ii plus programmer also worked well (at least in Win10). Can also be bought with many adapters for low cost (~80€/$) and has good chip support Supported ICs. GUI for this programmer is usable. WSON8 package can be soldered on SOIC8 adapter (PCB in my kit not testsocket) if a WSON adapter is not available, but recommend checking for shorted pins against thermal pad of WSON8 package before inserting the adapter in ZIF socket of programmer in this case.

Will also give the strapping resistor mod a try, and report what happens on my card.

For K3000M with last new bios, strapping modding not working.

Only K3100M with H5GQ2H24BFR need to be modded with strap config.