iM 4,1-14,4 iMac 2011 (see more) UEFI Firmware Mod

[countryhick]

Hi guys,

Would someone be able to outline the benefits of the "iGPU (IGD) full disable" patch?
Does this help with CPU temperatures?
Free up CPU processing power?
Or is there another reason?

Cheers
Andrew

 

[m0bil]

Hi guys,

Would someone be able to outline the benefits of the "iGPU (IGD) full disable" patch?
Does this help with CPU temperatures?
Free up CPU processing power?
Or is there another reason?

Cheers
Andrew

It will free some hardware resources: 128MB or 256MB shared ram (don't recall exactly) and a few irq/dma/dmi resources, but I doubt it will have any impact in cpu temp or processing power. The reason I did this patch is to avoid the annoying Windows BSOD when loading Intel Graphics Kernel Mode driver (igdkmd64.sys) after a windows install.

 

[man132]

Hi m0bil, thank you for your hardwork for this patch.

I want to ask, Does sleep in Imac 2011 with polaris card GPU work after applying this patch?

iMac 12,x iGPU (IGD) Full Disable patch

This firmware patch removes the Integrated Graphics Device (IGD, Bus 0 Device 2 Function 0) from the PCI bus.
The iGPU will not be initialized, will not be seen by OS nor use any hardware resources.

Behavior is the same as selecting "Disable Integrated Graphics" or "Disable onboard video" in other vendors bios.
As a side effect, it fixes the Windows BSOD when loading Intel Graphics Kernel Mode driver (igdkmd64.sys).

Notes:

• Tested on iMac 12,x with bootrom 87.0.0.0.0. May work on other Mac models and versions. If you try it watch UEFIPatch output for clues.
• Sleep works after applying patch.

I have started a Github repository to better keep track of firmware patches, this patch is there.

 

[m0bil]

Hi m0bil, thank you for your hardwork for this patch.

I want to ask, Does sleep in Imac 2011 with polaris card GPU work after applying this patch?

Yes, it does.

 

[Cloud9]

I applied the turbo overclock patch with a modified file for 42x (0x2A).


13% gain single-core and 17% in multicore performance on geekbench on my i7-2600 "non k"

System seems to be stable, but for that matter I need more testing time.

ThrottleStop reported PKg Power around 80w during Prime95 4c/8t (96.1w peak).


Before the patch I manage to reach just 65w... Maybe the original 21.5 bios had some sort of cap that forced the processor to downclock. Maybe thats why my results are above expected.


Throttling is an issue. With single/ dual core tasks the system sustains 4.0 to 4.2Ghz speeds, but with 4 cores within a couple of minutes the multiplier goes down... with fans at full blast and room temperature @24 oC the cores reached 85 oC (peak of 91 oC)

How are you hitting 4.0+ with a 2600 “non-k”?

 

[m0bil]

How are you hitting 4.0+ with a 2600 “non-k”?

It's not possible, non-k bins are fused at factory. Max speed for a non-k 2600 is 4x3800

 

[Cloud9]

Where can one find 2133 ddr3 so-dimms ?