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

[Nick [D]vB]

I just flashed my GTX 765M but stil have no Boot screen on W10. But that could be because of the EFI. But i benchmarked. And i noticed a lot higher Temperature while benchmarking.

View attachment 856397

Now first step done, now have to order the order some parts.

I think your Windows must also be installed in UEFI mode, so unless you re-install in legacy mode you won't get a boot screen without doing the bootrom mod. I'm surprised so many people use UEFI mode, do you not have BSOD crashes, and problems with sound drivers etc??

Thanks for the benchmarks, your temperatures are only higher because the card is now working at full speed, before it was locked in P5 "safe mode" under windows. You can probably clock it a lot higher but you need to watch the temperature, the card won't throttle down until it hits 93C !

 

[Roman78]

This is just a test installation to see if Windows would work. As so far i don't have any problems and no crashes. But how can you select the installation mode while installing? I thought it is installing in Legacy when the Bios is in Legacy mode and UEFI when the bios is set to UEFI. And i don't see any possibility to change that on an iMac. I could install it on a non Apple PC and than move the hard disk to the Mac in hoop it boots.

For gaming i have another Computer with a i7-4790K and and RX480. So i don't need to overclock.

 

[Nick [D]vB]

Out of interest can you check if your sound is working, or do you have a driver error 12 for HD Audio in device manager? Maybe microsoft have fixed that problem in the new Windows 10 update, I hope so because it was a real pain before, you had to enable 36bit address space with a DSDT registry patch to get sound working.

 

[FlorisVN]

I just flashed my GTX 765M but stil have no Boot screen on W10. But that could be because of the EFI. But i benchmarked. And i noticed a lot higher Temperature while benchmarking.

View attachment 856397

Now first step done, now have to order the order some parts.

maybe you are running Windows 10 in UEFI mode ?
I would advice running in legacy mode.
I had a bootscreen visible, but running win7 ultimate here..
(i also had a fully working bootcamp before i did the bootrom patch, and only the vbios mod)

see this quote from @Nick [D]vB above :

Boot screens only work in legacy Windows mode, run msinfo32 to check your BIOS boot mode.

If you install in UEFI mode you will have many problems on these iMacs, iGPU BSOD crashes etc

Do your iMac speakers work? I had to make a special patch to fix the HD audio driver in UEFI mode.

If you want to install in legacy mode you must use a DVD not USB stick, or modify the installer config.

 

[Nick [D]vB]

Yes, if you make a Windows USB installer it will use UEFI mode by default, but I think using a DVD installs in legacy mode on these iMacs. Another trick is to format the disk in MBR mode (NOT GPT) using diskutil or a windows PC and don't allow the Windows installer to re-format it when you select the disk as the install location.

 

[FlorisVN]

for anyone who is interessted, I made a very short and rough demo, about showing this vbios from Nick in action with a GTX765m.

Enjoy !

 

[FlorisVN]

Yes, if you make a Windows USB installer it will use UEFI mode by default, but I think using a DVD installs in legacy mode on these iMacs. Another trick is to format the disk in MBR mode (NOT GPT) using diskutil or a windows PC and don't allow the Windows installer to re-format it when you select the disk as the install location.

I think you are totally right here.
these machines are also made to use a dvd-player for bootcamp in the first place..
running in legacy bios mode the best for these macs, if you ask me...

 

[Nick [D]vB]

Thanks for making the video, now people know what to expect before doing the bootrom mod. I'm working on ways to reduce the initial delay between the chime and the screen waking up, I noticed it displays faster after doing an NVRAM reset or when holding Option for the boot-picker. I'm still experimenting but it seems to depend on the GPU type and maybe the disk configuration? It does seem faster / more robust on my 560X AMD card, and I seem to get fewer issues restarting from Mojave / Catalina than High Sierra. There might be some NVRAM variables we can set to improve things. Let me know if you find any bugs, I'll look into them when I get time.

 

[FlorisVN]

@Nick [D]vB ,

Ive just installed a new fresh on my test iMac.
I'm pretty sure this hs security update 004, will involve EFI firmware flashing.
I suppose this will brick the bootrom patch, I think.

I think you said before, just don't run these security updates.. ?
Am I correct here.. ?

I'm planning to trying to found out if I'm correct here..

what do you think. ?

 

[Nick [D]vB]

Go for it, you can just click update all. I tested this myself, I am sure it won't remove the bootrom mod.

 

[FlorisVN]

Go for it, you can just click update all. I tested this myself, I am sure it won't remove the bootrom mod.

ok, will test it soon..
thx !

I will post results here..

 

[atomizasser]

Hi
I'm ordered all material to upgrade my iMac 2010 to a GTX 765m. I'm interesting to apply all these patches to enjoy a full "apple" experience, but i have some doubts.
- Are the botroom mod applicable to iMac 2010?
- It is possible flash GTX in windows 7 in Parallels (no botcamp)
- I've tried to localize eeprom in my iMac following instructions by @Nick [D]vB . Is the chip select the correct one?


I used ROMTool to backup by botroom selecting the second option. It is correct?

 

[Nick [D]vB]

- Are the botroom mod applicable to iMac 2010?

Yes, it will work exactly the same on the 2010.

- It is possible flash GTX in windows 7 in Parallels (no bootcamp)

No, you must use real a Windows installation for nvflash to work,

but you could flash the graphics card using a programmer clip from MacOS.

- Is the chip select the correct one?

Yes, it's the same model code written on the EEPROM chip!

 

[wlagarde]

There is some foil grounding tape around that SD cable, if you remove it you can carefully separate the shield layers and get to the wires, so you can just tap off the 3.3v and keep using the SD reader if you need it, but if that's too tricky it is much easier just to cut the cable, or get the 3.3v form the PSU instead.

Thanks, you're very welcome, and a braver man than most! Here are a few tips that might help:

Use the original 6970M X-bracket, NOT the small 6770 / Nvidia type, No heat-sink mods are needed but it should’t hurt if you have already done that. I would use MacFanControl to increase the fan speed when running 3D apps, you can run this grep script to monitor real GPU temp under MacOS, and GPU-Z in windows.

while sleep 2; do ioreg -l |grep \"PerformanceStatistics\" | cut -d '{' -f 2 | tr '|' ',' | tr -d '}' | tr ',' '\n'|grep 'Temp\|Fan\|Clock'; done

What programmer did you get? The CH341A works great but the Windows software is garbage so I’ve attached Flashrom here, but if you're going to use MacOS you can just install it with brew.

I would check to make sure you have the latest Bootrom version before you patch it, if you have updated to the latest HS you should have that already and I doubt they will update it again. You can also use this tool to make a full bootrom back-up: http://dosdude1.com/apps/ROMTool.zip

But just keep that copy in a safe place, you must dump it again with the programmer and use that copy in UEFI Tool to do the mod. Be extra careful to make sure the test clip is on the right way around, putting it on backwards could damage the card / board! Unplug the iMac's AC and when you connect the clip you should see the first debug LED on the logic board light up green, then you know the clip is connected OK. You can also use the clip to flash the graphics card or just do that from Windows.

If you want to enable “iMac Pro” HEVC video acceleration in Mojave use the method shown here (the Lilu + WEG method does not work as well on the 580X) But that's only really worth doing if you do a lot of video work, FCPX etc. That’s everything I can think of for now, let me know if you have any questions, good luck with it! 8)

Nick many thanks my friend. I just flashed my GTX765m and 2011 iMac Boot Rom with your rom and mod method and indeed I get boot screens and the picker when holding option key. However, the screen will often not light until very late in the boot process (although sometimes it lights early). It only consistently lights from the very beginning when performing an NVRAM reset.

I used a CH341A programmer to complete the process. Worked like a charm.

My WX7100 comes next week. I'll try that next to see if its more consistent with backlight-on timing.

 

[FlorisVN]

Nick many thanks my friend. I just flashed my GTX765m and 2011 iMac Boot Rom with your rom and mod method and indeed I get boot screens and the picker when holding option key. However, the screen will often not light until very late in the boot process (although sometimes it lights early). It only consistently lights from the very beginning when performing an NVRAM reset.

I used a CH341A programmer to complete the process. Worked like a charm.

My WX7100 comes next week. I'll try that next to see if its more consistent with backlight-on timing.

it's still in beta, and if i am correct Nick is fully aware of this backlight timing issue.
it could be fixed someday

We have a working bootscreen now, which is awesome I think !

Keep in mind these AMD cards also need a hardware backlight mod, the nvidia kepler cards won't need that..
[doublepost=1567846340][/doublepost]

- Are the botroom mod applicable to iMac 2010?

Yes, it will work exactly the same on the 2010.

- It is possible flash GTX in windows 7 in Parallels (no bootcamp)

No, you must use real Windows installation for nvflash to work,

but you could flash the graphics card using a programmer clip from MacOS.

- Is the chip select the correct one?

Yes, it's the same model code written on the EEPROM chip!

I presume it will also work with 2009 iMac's aswell, about the bootrom patch part.. ?

 

[Zulus555]

Out of interest can you check if your sound is working, or do you have a driver error 12 for HD Audio in device manager? Maybe microsoft have fixed that problem in the new Windows 10 update, I hope so because it was a real problem before, you had to enable 36bit PCI address space with a DSDT registry patch to get sound working.

Windows is installed and works in UEFI mode. There were no BSODs for a month of work. Drivers are installed from drivers downloaded for Bootcamp. Drivers for Cirrus Logic CS4206A (AB 24) 6.6001.1.40. Performance gain with the new Vbios is approximately 15-20% in 3dmark. Temperature within 70 degrees Celsius.

 

[Polydactyl]

I can’t believe all the incredible work people are sharing on this thread. A bigs thanks to everyone, especially to Nick [DvB] for the GTX765 firmware.

Could someone please confirm a few things based on what I’ve read in the thread:

The optimal method of flashing bootrom on my iMac (27” 2010) is using a hardware programmer such as CH341A?

Once I’ve flashed my GTX765 with the updated VBIOS with Nick [DvB]‘s firmware and modified the bootrom, the backlight will work, but still be fixed at 100% and will require a hardware mod if I want to reduce the brightness?

Also, I should be receiving this later today. I assume it will be adequate for flashing both VBIOS and bootrom when used with a raspberry pi or a macbook?

Thanks!

 

[Pascal Baillargeau]

Great work Nick [DvB] and thanks for your shares. I will try all that in a month i think. For the moment i just can't unzip ROMTool, it ask me a password ?!?! is it normal?
Thanks in advance for your answers.

 

[NOTNlCE]

Great work Nick [DvB] and thanks for your shares. I will try all that in a month i think. For the moment i just can't unzip ROMTool, it ask me a password ?!?! is it normal?
Thanks in advance for your answers.

If you pulled from the dosdude site, the password is "rom" - as described in the zippasswords.txt file in the directory.

 

[wlagarde]

I can’t believe all the incredible work people are sharing on this thread. A bigs thanks to everyone, especially to Nick [DvB] for the GTX765 firmware.

Could someone please confirm a few things based on what I’ve read in the thread:

The optimal method of flashing bootrom on my iMac (27” 2010) is using a hardware programmer such as CH341A?

Once I’ve flashed my GTX765 with the updated VBIOS with Nick [DvB]‘s firmware and modified the bootrom, the backlight will work, but still be fixed at 100% and will require a hardware mod if I want to reduce the brightness?

Also, I should be receiving this later today. I assume it will be adequate for flashing both VBIOS and bootrom when used with a raspberry pi or a macbook?

Thanks!

Yes for all of your questions. I used my macbook air running windows 10 within vmware fusion.

 

[Nick [D]vB]

I presume it will also work with 2009 iMac's aswell, about the bootrom patch part.. ?

Maybe, but I can not test it. Their firmware is a bit older but the late 2009 27" with newer CPUs should be ok. I think the older ones with Core2 CPUs still had LVDS screens so they won't work, certainly not with the AMD cards. Not sure about the older 21" models either, but the 2011 should be ok?

I'm pretty sure this hs security update 004, will involve EFI firmware flashing.
I suppose this will brick the bootrom patch, I think.

I'm planning to trying to found out if I'm correct here..

I guess those updates went through ok?

Windows is installed and works in UEFI mode. There were no BSODs for a month of work. Drivers are installed from drivers downloaded for Bootcamp. Drivers for Cirrus Logic CS4206A (AB 24) 6.6001.1.40. Performance gain with the new Vbios is approximately 15-20% in 3dmark. Temperature within 70 degrees Celsius.

Cool, it looks like they fixed the UEFI mode problems then, but you will need to use Legacy mode to get a boot screen. You can easily convert a Legacy (MBR) windows install to UEFI (GPT) mode using a new microsoft tool, but unfortunately it doesn't work the other way around. You might be able to do it with 3rd party apps like Partition Wizard, it's a bit of a risk though so make a backup first.

Nick many thanks my friend. I just flashed my GTX765m and 2011 iMac Boot Rom with your rom and mod method and indeed I get boot screens and the picker when holding option key. However, the screen will often not light until very late in the boot process (although sometimes it lights early). It only consistently lights from the very beginning when performing an NVRAM reset.

I used a CH341A programmer to complete the process. Worked like a charm.

My WX7100 comes next week. I'll try that next to see if its more consistent with backlight-on timing.

Great you have tested the 765M to, the 580X will be quite an upgrade! I have attached an updated vBIOS and Bootrom mod for you to try, it might be slightly faster showing the boot-screen, and I noticed we now get the 3rd debug LED on the logic-board to light up (when the graphics EFI loads) which is nice to have for debugging.

You can mix & match with the old version to see what works best. Not sure what improvements AMD added in the base vBIOS update but it is slightly newer. I have found my 560X is definitely the most robust card when it comes to maintaining the boot-screen, not sure why but I think the vBIOS & EFI framebuffer are a closer match?

 

[passatgt]

Btw here is a great guide doing the vbios / bootrom flash using a raspberry pi + soic clip: https://www.ifixit.com/Answers/View/296157/What+GPU's+are+compatible+with+iMac+27"+2011#answer420333

I'm going to try both in my 27" + 780m

Is it possible that a bootrom mod would fix performance issues in a 2010 iMac equipped with a k1100m? Currently it performs the same(or even worse) as the factory HD4670 card, but based on benchmarks it should be a LOT faster.

 

[Nick [D]vB]

Is it possible that a bootrom mod would fix performance issues in a 2010 iMac equipped with a k1100m?

Sadly not, the performance fixes are in the vBIOS and are different for every card. It's not really possible to fix them without a card to test with because it's very easy to brick the card. A partial work-around is to use Nvidia Inspector to overclock the P5 state, but that only works in windows, and the memory will still be slower.

If you are getting much lower performance you should use Intel Power Gadget (or CPU-Z etc) to check your CPU clocks are not stuck at 1600MHz. The iMac SMC firmware can go into "safe mode" if it detects a fault with the fans, temp sensors, or the PSU. This will also lock the GPU clocks to the lowest level (even on my fixed cards) until you fix the problem. Sometimes an SMC / NVRAM reset is also needed to restore full performance.

 

[caxias_Brazil]

Hello.
I have an iMac mid 2011 where the amd radeon 6970M has always been having problems.

I would like to exchange for a GTX but:

Does anyone have model eBay for me to buy one?

Any tutorial on how can I change the video card?

After installing the video card can I just plug in my iMac and use it on High Sierra?

Thank you!

I will follow the forum for future updates.

 

[wlagarde]

Hello.
I have an iMac mid 2011 where the amd radeon 6970M has always been having problems.

I would like to exchange for a GTX but:

Does anyone have model eBay for me to buy one?

Any tutorial on how can I change the video card?

After installing the video card can I just plug in my iMac and use it on High Sierra?

Thank you!

I will follow the forum for future updates.

https://www.ebay.com/itm/5YPW3-9R3F...182286?hash=item3fcae89ece:g:XCwAAOSwGW1daY2m

Also read through the very beginning post on this thread.