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

idenis42 · Jul 26, 2021

edwardgeo said:
You can try 570 ELLESMERE Vbios, That is rough and temporary solution, but practically its apple vbios and can be great for test boot. Anyway i cant find RX4xx vbioses for high TDP gpu. If you get it working, then you need to find OEM vbios. Sorry i just get lost with various count of vbioses. As i remember, the GPU arrived with custom vbios?

But I don't compare your onboard VRAM with vbioses content. Open with polaris bios editor only for compare vram IC labels. The vram is more important than voltages, etc. It could fail to initialize

The video card came with the original BIOS. I have sent you the original bios above. I can give the original bios again.
Now I will check 570 ELLESMERE and let you know.
https://forums.macrumors.com/attachments/orig-480rx-zip.1810762/ - original vbios

pedromm00042 · Jul 26, 2021

nikey22 said:
** NVIDIA Quadro K610M Mac edition ROM **

View attachment 1726139

K610M:
The chip I used to develop the ROM is: N15M-Q2-B-A1
MXM-A (3.0) bus interface, low powered card at TDP 30W.
It is a drop-in fit for the 21.5" iMac and 27” iMac heatsinks.
It is based on the GK208 GPU Kepler 2.0 architecture.
Metal supported.

I put this together only because there are now a few members on here that have one and it is relatively cheap to purchase for the moment.
I have not had a chance to test it fully, but I can confirm brightness control will work with Opencore implementation on High Sierra 10.13.6. It is based on Nick[D]vb's ROMs, credits to him.
Bootpicker menu is also available ofcourse.

I've noticed that brightness is not set correctly when using the Opencore platform:

Code:

<key>DeviceProperties</key> <dict> <key>Add</key> <dict> <key>PciRoot(0x0)/Pci(0x1,0x0)/Pci(0x0,0x0)</key> <dict> <key>@0,backlight-control</key> <data>AQAAAA==</data> <key>@0,built-in</key> <data>AQAAAA==</data> </dict> <key>PciRoot(0x0)/Pci(0x3,0x0)/Pci(0x0,0x0)</key> <dict> <key>@0,backlight-control</key> <data>AQAAAA==</data> <key>@0,built-in</key> <data>AQAAAA==</data> </dict> </dict> <key>Delete</key> <dict/> </dict>

The first <key> PciRoot(0x0)/Pci(0x1,0x0)/Pci(0x0,0x0) is made up of the Root PCI Bridge, the 1st PCI Device node and 2nd PCI Device node.

The second <key> entry is similarly encoded for the 2009/2010 machines.

Correlating this with the IO reg entry:
in 2011 models:
IOACPIPlane:/_SB/PCI0@0/POP2@10000/GFX0@0
in 2009/2010 models:
IOACPIPlane:/_SB/PCI0@0/POP2@30000/GFX0@0

I suggest the following changes:
delete the entire second key below for those of you with a 2011 machine:

Code:

<key>PciRoot(0x0)/Pci(0x3,0x0)/Pci(0x0,0x0)</key> <dict> <key>@0,backlight-control</key> <data>AQAAAA==</data> <key>@0,built-in</key> <data>AQAAAA==</data> </dict>

This cleared up the brightness issue for me.

Insanely Great!
-Steve Jobs

******
UPDATE
******
02/06/2021
-minor rom changes, improved speed, TDP: 1097Mhz, boost: 1202Mhz, Mem:1600Mhz
-working on Catalina 10.15.7 2011 iMac 21.5"
-working on Catalina 10.15.7 2009 iMac 27"

07/15/2020
- working on Catalina 10.15.3 2011 iMac 21.5"
- no internet recovery
- working on Catalina 10.15.X 2009 iMac 27" (Ausdauersportler)

Hi @nikey22, i have same GPU nVIDIA k610m N15M-Q2-B-A1, i flashed bios with this ROM with CH341a programer, but still no working on imac 2010 27". Keep black screen when power on. There are a mod to do in rom to work in imac 2010 27"?

Ausdauersportler · Jul 26, 2021

Some HP BIOS versions I pulled from some cards. I have not inspected these BIOS versions or tested them

idenis42 · Jul 26, 2021

edwardgeo, Ausdauersportler - ALL VBIOS DOES NOT WORK 😕😣😖😫

the throttle in the video card is suspicious.

Ausdauersportler · Jul 26, 2021

idenis42 said:
View attachment 1811051

edwardgeo, Ausdauersportler - ALL VBIOS DOES NOT WORK 😕😣😖😫
the throttle in the video card is suspicious.

This is not really surprising. Do all vBIOS versions show the same symptoms as in your video? Currently the best guess is a hardware mod like the HP WX4150 needed to run in the iMac12,2.

Your RX480 will run perfectly in the Mid 2010 and Late 2009. We have tested these cards for nearly a year, now.

idenis42 · Jul 26, 2021

Ausdauersportler said:
This is not really surprising. Do all vBIOS versions show the same symptoms as in your video? Currently the best guess is a hardware mod like the HP WX4150 needed to run in the iMac12,2.

Your RX480 will run perfectly in the Mid 2010 and Late 2009. We have tested these cards for nearly a year, now.

The symptoms are the same.

Nguyen Duc Hieu · Jul 26, 2021

I tested my HP WX4150 4GB today after upgrading to Big Sur 11.5 (iMac 27" 2010; still at OCLP 0.1.6 I guess)
- Big Sur 11.5 runs smoothly, but camera and microphone don't work on Messenger and MS Team.
- The Windows USB enclosure hang-up (still working well on another HP PC)
- High Sierra still got the black screen if running on internal display only. (OCLP showed the menu, verbose mode, then black-out). Need to connect external display or dummy load to trigger the LCD light.
- Target Display Mode worked automatically (High Sierra). Mac Fan control in High Sierra did work, keeping the machine runs quiet. The display are at max brightness, but can be reduced by Intel HD Graphic Control panel (software simulation, not real LCD PWM like from Mac OS).
When both the PC and iMac are in sleep mode, it's necessary to wake the iMac first, then the PC to maintain Target Display Mode.

idenis42 · Jul 26, 2021

Ausdauersportler said:
This is not really surprising. Do all vBIOS versions show the same symptoms as in your video? Currently the best guess is a hardware mod like the HP WX4150 needed to run in the iMac12,2.

Your RX480 will run perfectly in the Mid 2010 and Late 2009. We have tested these cards for nearly a year, now.

1-The computer turns on without a video card.
2-I erased the bios. The computer does not turn on.
I realized that this is not a bios. And the video card has a different scheme.
I'm finishing the experiment. I will send the video card to the seller. Thanks for the help.

jowaju · Jul 26, 2021

Mischa85 said:
For the iMac9,1, which uses LVDS: It might be possible to produce a working NVIDIA VBIOS using the DCB tables I posted in that post. The GeForce 9400M VBIOS is ripped from an actual iMac9,1. Please also dump the VBIOS of that GT130. The DCB tables should be the same of the GeForce 9400 VBIOS I used for that.

I myself am kinda stuck as I have an iMac10,1, I want to replace the GPU on. This uses DP but for some reason it still doesn't work with the VBIOSses posted here. I need the iMac10,1 GeForce 9400M VBIOS for proper investigation, but I did not acquire it yet.

I have an iMac 10,1 here that is working with a 9400m video card. Tell me exactly what you need and I'll see if I can get it to you before I have to send the machine down the line.

edwardgeo · Jul 26, 2021

idenis42 said:
1-The computer turns on without a video card.
2-I erased the bios. The computer does not turn on.
I realized that this is not a bios. And the video card has a different scheme.
I'm finishing the experiment. I will send the video card to the seller. Thanks for the help.

Sad story... but if you have a scanner, you can try to make i high quality images for future research. If @Ausdauersportler is right, then we can try manage what is wrong. And that’s somehow related to power. Or even the delay of power controller initialization. Anyway the wx4150 is related to powering gpu, and this is a software problem. Macs are fully different from pc in case of pci host initializing.

Ausdauersportler · Jul 26, 2021

jowaju said:
I have an iMac 10,1 here that is working with a 9400m video card. Tell me exactly what you need and I'll see if I can get it to you before I have to send the machine down the line.

I lost track if we still have the vBIOS, but just in case:

Grab the latest GRML Linux flash utility (first post, FAQ, flashing), create an bootable USB stick, boot it, save the vBIOS of the card using the nvflash_linux onto the USB (this is possible now) as described in the posts and publish the vBIOS here.

You can work directly on you iMac10,1, there is no need to use SSH and login remotely als long as your iMac is working properly.

Thanks in advance!

(I hope it is that easy, never had an iMac with an integrated GPU)

idenis42 · Jul 26, 2021

edwardgeo said:
Sad story... but if you have a scanner, you can try to make i high quality images for future research. If @Ausdauersportler is right, then we can try manage what is wrong. And that’s somehow related to power. Or even the delay of power controller initialization. Anyway the wx4150 is related to powering gpu, and this is a software problem. Macs are fully different from pc in case of pci host initializing.

I have already sent the video card back to the seller.

Alex W. · Jul 26, 2021

I have a 27" with a 6770m, will i need to purchase a 3 heat pipe along with the gpu or do the 6770m units come with 3 pipes?

Nguyen Duc Hieu · Jul 26, 2021

Alexander William said:
I have a 27" with a 6770m, will i need to purchase a 3 heat pipe along with the gpu or do the 6770m units come with 3 pipes?

We don't know. Only your seller knows.

The_Croupier · Jul 27, 2021

Alexander William said:
I have a 27" with a 6770m, will i need to purchase a 3 heat pipe along with the gpu or do the 6770m units come with 3 pipes?

I'm Pretty sure only the iMacs that came with the 6970 have the 3 pipe heatsink.

Why don't you open you iMac and check what heatsink you have?

dfranetic · Jul 27, 2021

Alexander William said:
I have a 27" with a 6770m, will i need to purchase a 3 heat pipe along with the gpu or do the 6770m units come with 3 pipes?

AFAIK the HD 6770M came with a 2 heatpipe heatsink for smaller MXM-A cards. It is therefore suitable for MXM-A cards - so it depends on which ‘replacement’ card you plan use.

unclemiltie · Jul 27, 2021

Alexander William said:
I have a 27" with a 6770m, will i need to purchase a 3 heat pipe along with the gpu or do the 6770m units come with 3 pipes?

My 27" 2011 iMac with a 6770 has a 2-pipe heat sink in it. My 27" 2011 imac with a 6970 has a 3 pipe heat sink in it (and is now running with a K3100m in place of the failed 6970)

to use one of the higher power cards you will need the bigger heat sink

RTouris · Jul 28, 2021

..double post / please delete

RTouris · Jul 28, 2021

RTouris said:
Just received an iMac pre-flased K3000M today after a long wait over the post; Wondering if I should possibly even attempt to install this in a 27'' late 2009 or it's a guaranteed DOA...To the untrained eye I suppose we' re looking at a significant (water?) damage in an area on the top left hand side of the 'underside', while in closing-in one can see that one of the chip's connection-legs looks substantially battered up in what appears to be a charcoal material state...

Seller obviously advertised this as a fully functional pre-tested unit as they all do in similar Ali ads. In await of an alt. 2-pipe heatsink - since I'd be performing another such upgrade on a similar setup in the near future - evaluating my next steps. Seller comms sent, in await of his take on this, but I have a feeling this won't end well..

Looking for an experienced opinion before I embark on this 'quest'..

An update on this.

First K3000M proved to be DOA, no video / impossible to flash since system wouldn't recognise. Seller only offered a $5 refund, so I opened a dispute on Ali who only authorised a $15 due to the fact that I didn't present the case with an installation video - despite the seller also not providing evidence that the card was working as advertised. Kept card as a donor.

Second card also a K3000M from alt. vendor through eBay didn't come preflashed, had to go down the xanderon USB SSH route - pretty straightforward - flashed ST3PHL3's ROM onto it. Card appears to work OK on Mojave (after all relevant patches applied) - i.e. native boot screen and brightness control, no sleep issues, no weird artifacts on screen and all.

Initial comparison of GPU heatsink temps / MXM amperage drawn - compared to previously installed AMD Radeon HD4850 (in parentheses)

- in idle: ~45ºC / 0.5A respectively (55ºC / 1.6A)
- while stress testing (Valley): ~70-75ºC / 3.15A respectively (~80º-85ºC / 3.15A)

Unigine's Valley scores at (min/avg/max - score) 12/18.5/35-770 are only slightly better compared to the HD4850's at 7/15/24.5-630 and substantially lower to the scores of other K3000Ms I've seen posted on similarly spec'ed systems at 15/28/52-1170.

There's however an emerging pattern of only a few instances when the card can boost up to the 50W TDP of the MXM interface. Most of the times it can only draw upto a max of ~1.15A in which case the benchmark performance is much lower than that of the previously installed Radeon and consequently a Valley benchmark yields 4/6.5/11-270 (!!).

Using MetalBench v.1.0 in underperforming mode (amperage @ ~1.15A) I get an average of ~30MRays/sec and lots of pink artifacts with the framerate all over the place, while in full-amperage mode (3.05-3.15A) I get a sustained ~300MRays/sec.

I consider flashing @nikey22 's ROM on it to see how it behaves, although I'm not expecting miracles...As always feel free to chime in in case this behaviour is reminiscent of impending trouble.

P.S.: I did get a few reboots while stressing the card for a few minutes about a week ago, which have not been replicated ever since.

RT.-

edwardgeo · Jul 28, 2021

nikey22 said:
sub system ID: 103C 80D5

let's break it down and decode it:

HP: 0x103C x 4 = 0x40F0 + 2 = 0x40F2 --> 22 0F 44 ( with a half byte, the HEX code in the header highlighted tag 2)
HP: 0x80D5 x 2 = 0x101AA, carry over the half byte 1 = AA 01 21 (the HEX code in the header highlighted tag 1)

ATOM BIOS Header
View attachment 1809705

Hi, Nick! Did you try to decode header of rom? I mean the part of the file you already partially decode?

I successfully done dmem dump of zbook and what is important, the mxm vbios isn’t shadowed at all. So maybe it’s security hp feature, or possibly the pei instructions to inject only system bios option rom. Did someone tried to dump option rom addresses of iMac on custom gpu? The vbios rom start at dmem c0000 2000 in efishell64. Is it possible to modify option rom at Apple system bios rom? And does custom gpu have issues with EC fan controller?

The_Croupier · Jul 28, 2021

RTouris said:
An update on this.

First K3000M proved to be DOA, no video / impossible to flash since system wouldn't recognise. Seller only offered a $5 refund, so I opened a dispute on Ali who only authorised a $15 due to the fact that I didn't present the case with an installation video - despite the seller also not providing evidence that the card was working as advertised. Kept card as a donor.

Second card also a K3000M from alt. vendor through eBay didn't come preflashed, had to go down the xanderon USB SSH route - pretty straightforward - flashed ST3PHL3's ROM onto it. Card appears to work OK on Mojave (after all relevant patches applied) - i.e. native boot screen and brightness control, no sleep issues, no weird artifacts on screen and all.

Initial comparison of GPU heatsink temps / MXM amperage drawn - compared to previously installed AMD Radeon HD4850 (in parentheses)

- in idle: ~45ºC / 0.5A respectively (55ºC / 1.6A)
- while stress testing (Valley): ~70-75ºC / 3.15A respectively (~80º-85ºC / 3.15A)

Unigine's Valley scores at (min/avg/max - score) 12/18.5/35-770 are only slightly better compared to the HD4850's at 7/15/24.5-630 and substantially lower to the scores of other K3000Ms I've seen posted on similarly spec'ed systems at 15/28/52-1170.

There's however an emerging pattern of only a few instances when the card can boost up to the 50W TDP of the MXM interface. Most of the times it can only draw upto a max of ~1.15A in which case the benchmark performance is much lower than that of the previously installed Radeon and consequently a Valley benchmark yields 4/6.5/11-270 (!!).

Using MetalBench v.1.0 in underperforming mode (amperage @ ~1.15A) I get an average of ~30MRays/sec and lots of pink artifacts with the framerate all over the place, while in full-amperage mode (3.05-3.15A) I get a sustained ~300MRays/sec.

I consider flashing @nikey22 's ROM on it to see how it behaves, although I'm not expecting miracles...As always feel free to chime in in case this behaviour is reminiscent of impending trouble.

P.S.: I did get a few reboots while stressing the card for a few minutes about a week ago, which have not been replicated ever since.

RT.-

Sounds like your CPU might be throttling, what’s your geekbench5 score?

Ausdauersportler · Jul 28, 2021

RTouris said:
An update on this.

First K3000M proved to be DOA, no video / impossible to flash since system wouldn't recognise. Seller only offered a $5 refund, so I opened a dispute on Ali who only authorised a $15 due to the fact that I didn't present the case with an installation video - despite the seller also not providing evidence that the card was working as advertised. Kept card as a donor.

Second card also a K3000M from alt. vendor through eBay didn't come preflashed, had to go down the xanderon USB SSH route - pretty straightforward - flashed ST3PHL3's ROM onto it. Card appears to work OK on Mojave (after all relevant patches applied) - i.e. native boot screen and brightness control, no sleep issues, no weird artifacts on screen and all.

Initial comparison of GPU heatsink temps / MXM amperage drawn - compared to previously installed AMD Radeon HD4850 (in parentheses)

- in idle: ~45ºC / 0.5A respectively (55ºC / 1.6A)
- while stress testing (Valley): ~70-75ºC / 3.15A respectively (~80º-85ºC / 3.15A)

Unigine's Valley scores at (min/avg/max - score) 12/18.5/35-770 are only slightly better compared to the HD4850's at 7/15/24.5-630 and substantially lower to the scores of other K3000Ms I've seen posted on similarly spec'ed systems at 15/28/52-1170.

There's however an emerging pattern of only a few instances when the card can boost up to the 50W TDP of the MXM interface. Most of the times it can only draw upto a max of ~1.15A in which case the benchmark performance is much lower than that of the previously installed Radeon and consequently a Valley benchmark yields 4/6.5/11-270 (!!).

Using MetalBench v.1.0 in underperforming mode (amperage @ ~1.15A) I get an average of ~30MRays/sec and lots of pink artifacts with the framerate all over the place, while in full-amperage mode (3.05-3.15A) I get a sustained ~300MRays/sec.

I consider flashing @nikey22 's ROM on it to see how it behaves, although I'm not expecting miracles...As always feel free to chime in in case this behaviour is reminiscent of impending trouble.

P.S.: I did get a few reboots while stressing the card for a few minutes about a week ago, which have not been replicated ever since.

RT.-

Did you reinstall Mojave using OCLP? There is no need to patch anything at all using this method on iMac11,x systems.

nikey22 · Jul 28, 2021

@edwardgeo
This is what I do to locate the shadowed vbios in an imac.

First, let's take a look at all of our devices in our computer that are managed by EFI drivers and locate GPU entry:

Code:

fs6:\> devices -b

result:

Rich (BB code):

C  T   D
T  Y C I
R  P F A
L  E G G #P #D #C Device Name
== = = = == == == =============================================================
34 R - -  -  1 31 Acpi(PNP0A03,0)
A5 D - -  4  -  - Primary Console Input Device
A6 D - -  1  -  - Primary Console Output Device
F9 D - -  1  -  - Acpi(PNP0A03,0)/Pci(0|0)
FA D - -  1  -  - Acpi(PNP0A03,0)/Pci(3|0)
FB B - -  1 5 1  ATI Radeon Blackcomb Video Adapter       <--what we want
FC D - -  1  -  - Acpi(PNP0A03,0)/Pci(3|0)/Pci(0|1)
FD D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|0)
FE D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|1)
FF D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|2)
........
.....
..

Next, let's look at the device handles in the EFI environment:

Rich (BB code):

fs6:\> dh -b FB

Result:

Rich (BB code):

..
...
....
ConOut (0)
   PciIo (BEB41D28)
     Segment #.....: 00
     Bus #.........: 01
     Device #......: 00
     Function #....: 00
     ROM Size......: 1BA00                         <--what we want
     ROM Location..: BDF50018                      <--what we want

now, dump the entire vbios into a file:

Rich (BB code):

dmem BDF50018 1BA00 > imac_vbiosdump.rom

Result:

Code:

  Memory Address 00000000BDF50018 1BA00 Bytes
  BDF50018: 55 AA 80 E9 3D 02 00 00-00 00 00 00 00 00 00 00  *U...=...........*
  BDF50028: 00 00 00 00 00 00 00 00-F0 01 00 00 00 00 49 42  *..............IB*
  BDF50038: 4D 42 00 00 00 00 00 00-00 00 00 00 00 00 00 04  *MB..............*
  BDF50048: 20 37 36 31 32 39 35 35-32 30 00 00 00 00 00 00  * 761295520......*
  BDF50058: 35 02 00 00 00 00 00 00-CC 01 00 00 00 00 00 00  *5...............*
  BDF50068: 30 36 2F 30 37 2F 31 31-2C 31 32 3A 33 36 3A 30  *06/07/11,12:36:0*
  BDF50078: 36 00 00 00 E9 D0 03 00-E9 DF 03 00 00 00 A8 00  *6...............*
  BDF50088: 00 00 00 00 00 16 00 80-00 02 00 00 00 00 00 00  *................*
  BDF50098: D6 20 00 00 00 00 00 00-00 00 00 00 00 00 00 00  *. ..............*
  BDF500A8: 00 00 00 00 00 00 00 00-00 00 00 00 20 67 00 00  *............ g..*
  BDF500B8: 00 00 00 00 00 00 00 00-31 31 33 2D 43 32 39 36  *........113-C296*
.......
....
...
..

Can be done with any of the devices onboard

RTouris · Jul 28, 2021

The_Croupier said:
Sounds like your CPU might be throttling, what’s your geekbench5 score?

That'd be 537/1622 https://browser.geekbench.com/v5/cpu/9047047 - pretty average for such a system. I'm leaning towards a GPU fault / BIOS incompatibility at this stage given the fact that iStat shows the MXM module not exceeding ~1A most of the times when benchmarking. On the other hand HWmonitor reports fixed frequencies of 162 (!) / 648Mhz for the GPU core / memory respectively with no throttling up or down which is kinda weird if you ask me...This is a patched Mojave installation. OCLP on a separate clean partition gives the exact same results.

edwardgeo · Jul 28, 2021

nikey22 said:

@edwardgeo
This is what I do to locate the shadowed vbios in an imac.
Let's take a look at all of our devices in our computer and locate your GPU entry:

Code:

devices -b

result:

Code:

34 R - -  -  1 31 Acpi(PNP0A03,0)
A5 D - -  4  -  - Primary Console Input Device
A6 D - -  1  -  - Primary Console Output Device
F9 D - -  1  -  - Acpi(PNP0A03,0)/Pci(0|0)
FA D - -  1  -  - Acpi(PNP0A03,0)/Pci(3|0)
FB B - -  1  5  1 ATI Radeon Blackcomb Video Adapter     <-- what we want
FC D - -  1  -  - Acpi(PNP0A03,0)/Pci(3|0)/Pci(0|1)
FD D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|0)
FE D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|1)
FF D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|2)
100 D - -  1  -  - Acpi(PNP0A03,0)/Pci(8|3)

Next, let's look at the device handles in the EFI environment:

Code:

dh -b FB

Result:

Code:

   ConOut (0)
   PciIo (BEB41D28)
     Segment #.....: 00
     Bus #.........: 01
     Device #......: 00
     Function #....: 00
     ROM Size......: 1BA00                         <--what we want
     ROM Location..: BDF50018                      <--what we want

now, dump the entire vbios into a file:

Code:

dmem BDF50018 1BA00 > imac_vbiosdump.rom

Result:

Code:

  Memory Address 00000000BDF50018 200 Bytes
  BDF50018: 55 AA 80 E9 3D 02 00 00-00 00 00 00 00 00 00 00  *U...=...........*
  BDF50028: 00 00 00 00 00 00 00 00-F0 01 00 00 00 00 49 42  *..............IB*
  BDF50038: 4D 42 00 00 00 00 00 00-00 00 00 00 00 00 00 04  *MB..............*
  BDF50048: 20 37 36 31 32 39 35 35-32 30 00 00 00 00 00 00  * 761295520......*
  BDF50058: 35 02 00 00 00 00 00 00-CC 01 00 00 00 00 00 00  *5...............*
  BDF50068: 30 36 2F 30 37 2F 31 31-2C 31 32 3A 33 36 3A 30  *06/07/11,12:36:0*
  BDF50078: 36 00 00 00 E9 D0 03 00-E9 DF 03 00 00 00 A8 00  *6...............*
  BDF50088: 00 00 00 00 00 16 00 80-00 02 00 00 00 00 00 00  *................*
  BDF50098: D6 20 00 00 00 00 00 00-00 00 00 00 00 00 00 00  *. ..............*
  BDF500A8: 00 00 00 00 00 00 00 00-00 00 00 00 20 67 00 00  *............ g..*
  BDF500B8: 00 00 00 00 00 00 00 00-31 31 33 2D 43 32 39 36  *........113-C296*
.......
....
...
..

Can be done with any of the devices onboard

We few minutes ago get to this idea with @hugodlc, that shadow vbios can be in acpi bios space of ram!

You’re awesome! Nick, thank you for this short tutorial!

So you dump vbios of old amd gpu, what’s the model you have?

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edwardgeo, Ausdauersportler - ALL VBIOS DOES NOT WORK 😕😣😖😫

edwardgeo, Ausdauersportler - ALL VBIOS DOES NOT WORK 😕😣😖😫