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

[rcfortugno]

Hey guys,

I bought a 765m for my late 2009 27" iMac. After installing I tried booting, I get the boot sound and it seems like the computer is starting but the screen stays black. I put the original ATI card back in and it boots just fine. My thought is either the card is faulty or it requires a VBIOS flash. I went ahead and ordered a CH341a programmer from Amazon ($15) and I was going to use Nick's VBIOS file. Do I still have to install windows or can I transfer this file to the CH341a programmer and flash it directly to the 765m?

 

[Ausdauersportler]

Hey guys,

I bought a 765m for my late 2009 27" iMac. After installing I tried booting, I get the boot sound and it seems like the computer is starting but the screen stays black. I put the original ATI card back in and it boots just fine. My thought is either the card is faulty or it requires a VBIOS flash. I went ahead and ordered a CH341a programmer from Amazon ($15) and I was going to use Nick's VBIOS file. Do I still have to install windows or can I transfer this file to the CH341a programmer and flash it directly to the 765m?

Yes, you can! Read post #1 of this thread and follow all the links there describing the flash methods or go back some pages to post #4363 and try out this linux usb stick/sd card method to write the BIOS. I used the CH341A and checked recently out of curiosity the linux boot stick version. Both are fine. Anyway you need a linux host or a mac with mojave or catalina and hombrew to get the flashprom software running. it uses your CH341A....

BTW: late 2009 with core 2 duo will not work according to different sources here

 

[rcfortugno]

Yes, you can! Read post #1 of this thread and follow all the links there describing the flash methods or go back some pages to post #4363 and try out this linux usb stick/sd card method to write the BIOS. I used the CH341A and checked recently out of curiosity the linux boot stick version. Both are fine. Anyway you need a linux host or a mac with mojave or catalina and hombrew to get the flashprom software running. it uses your CH341A....

BTW: late 2009 with core 2 duo will not work according to different sources here

Thanks for the reply! I have a Core i7 Late 2009 so I'm hopeful that it will work!

 

[LegoNickD]

We are using the Open Core bootloader that was based on @Rastafabi Mac Pro's bootloader. It's cloned over to look like a Time Machine Drive. Not 100% sure why we couldn't make it internal if we wanted too. I think if being booted from internal EFI partition it has the chance of damaging the iMacs bootrom like Clover did, I don't want to screw around with that. The best way I boot Open Core with my iMacs is with an SD card so it doesn't use up any of my USB ports.

I don't think there should be any issue with an internal efi partition since that's how you boot apfs on 2008/9, the main issue comes from clover spoofing some stuff with the board that patching things that should not be changed on real Macs (sorry for being vague I couldn't find any real answers for how it actually breaks on google). Open core on the internal drive shouldn't be any different than on an external drive.

 

[NOTNlCE]

NOTNICE - Thank you for testing the potential for 4K output. Much appreciated. Pity it did not work.

It was my adapter. mDP adapter to DP on my Acer B286HK gives me full 4K@60Hz on my 27" 2011 with K1100M.

 

[JessieComputes]

NOTNICE - That is very interesting. I was only hoping for 30Hz, but to get the full 60Hz is pretty amazing.

 

[FlorisVN]

Hey guys,

I bought a 765m for my late 2009 27" iMac. After installing I tried booting, I get the boot sound and it seems like the computer is starting but the screen stays black. I put the original ATI card back in and it boots just fine. My thought is either the card is faulty or it requires a VBIOS flash. I went ahead and ordered a CH341a programmer from Amazon ($15) and I was going to use Nick's VBIOS file. Do I still have to install windows or can I transfer this file to the CH341a programmer and flash it directly to the 765m?

remember there is still a efi bootscreen delay in nicks current vbios beta.
When you start the iMac using alt key (option) takes about 4-5 seconds sometimes to show the efi bootscreen.

if the vbios is also successfully working, you can also check this by opening about this mac or system profiler.
The gpu info should say the mod was by Nick inside the gpu name string within MacOS.

 

[tgaillar]

Hi there,

Quick Quadro K1x00M question (searched the whole forum but could not find a clear answer): is there any requirement on the amount of VRAM a Quadro K1x00M shall have with respect to @Nick [D]vB vbios? These boards are commonly found with 2GB, but there are also some available on the market with 1GB. Will the latter (1GB) work to with @Nick [D]vB vbios?

Thank you

 

[Ausdauersportler]

Hi there,

Quick Quadro K1x00M question (searched the whole forum but could not find a clear answer)

Thank you

Cannot answer explicitly but I recommend getting a K1100M or K2100M (which I have seen with 2GB, only) because only these will have according to post #1 a working backlight control, soon.

 

[SKYNET-1]

I am not sure what you are asking. I don't believe anyone here has tried to use a GTX 880M, though with the correct VBIOS it may work. Typically the "Dell" or "Alienware" VBIOS for these cards support the internal eDP connector by default. There is no modified VBIOS for boot screens at the moment.

will try a dell/alienware 880 ist just a 780 with 8GB VRam, same chip(GK104)... and i picked up the 27" yesterday, so now i want the maximum i can get

btw. somebody here said maxwell not will work... but the 860M and 850M are GM107 = maxwell(only the 870 & 880 is kepler --> GK104)... so what is the difference between the "small" maxwell cards and big maxwell cards like 970 & 980?

 

[Ausdauersportler]

will try a dell/alienware 880 ist just a 780 with 8GB VRam, same chip(GK104)... and i picked up the 27" yesterday, so now i want the maximum i can get

btw. somebody here said maxwell not will work... but the 860M and 850M are GM107 = maxwell(only the 870 & 880 is kepler --> GK104)... so what is the difference between the "small" maxwell cards and big maxwell cards like 970 & 980?

That is not entirely true:

Review Nvidia GeForce GTX 860M Maxwell vs. Kepler

Comparison of the GeForce GTX 860M (Maxwell vs. Kepler)

www.notebookcheck.net

There are cards with the same brand and type name and different chips on the market. Since Apple has only used cards with the Kepler chip the drivers within MacOS will work only with the these cards. No Maxwell. I am only resending what has already been discussed in length in the former posts - somewhere

 

[NOTNlCE]

will try a dell/alienware 880 ist just a 780 with 8GB VRam, same chip(GK104)... and i picked up the 27" yesterday, so now i want the maximum i can get

btw. somebody here said maxwell not will work... but the 860M and 850M are GM107 = maxwell(only the 870 & 880 is kepler --> GK104)... so what is the difference between the "small" maxwell cards and big maxwell cards like 970 & 980?

NVIDIA did something a bit backwards with Maxwell. Rather than releasing the top tier cards for the architecture first, they released the low power cards as a "proof of concept" to show how much less power the architecture draws. The desktop GTX 750 Ti~ cards were released first then 900 series cards were beefed up. There's minimal difference as far as we're concerned - if the GPU has a Maxwell core, there are no drivers for it in macOS.

If you are looking for maximum performance, the RX 580 MXM is currently the most powerful card you can put in one of these guys, but it requires a few extra tweaks. See the front page toward the bottom under "Experimental" for more info.

 

[SKYNET-1]

NVIDIA did something a bit backwards with Maxwell. Rather than releasing the top tier cards for the architecture first, they released the low power cards as a "proof of concept" to show how much less power the architecture draws. The desktop GTX 750 Ti~ cards were released first then 900 series cards were beefed up. There's minimal difference as far as we're concerned - if the GPU has a Maxwell core, there are no drivers for it in macOS.

If you are looking for maximum performance, the RX 580 MXM is currently the most powerful card you can put in one of these guys, but it requires a few extra tweaks. See the front page toward the bottom under "Experimental" for more info.

thx guys, was new for me there r two different 860M... i hate when companies do that, so u not can buy a 860M except u know its a maxwell or a kepler

n the problem with the 9xx series n above was, only works with external display, no matter windows, linux or OSX is running on the machine, right?

n i really would like to use a RX580, but all the issues... urgh... works the RX580 well with windows via bootcamp?

 

[Kouiderdream]

thx guys, was new for me there r two different 860M... i hate when companies do that, so u not can buy a 860M except u know its a maxwell or a kepler

n the problem with the 9xx series n above was, only works with external display, no matter windows, linux or OSX is running on the machine, right?

n i really would like to use a RX580, but all the issues... urgh... works the RX580 well with windows via bootcamp?

Hi
Its intéressant to know if the gtx 880m woks in imac 2011 27 even if no boot screen but if internal screen works its a good oportunity , to go fast because at the moment ther is no more wx7100 to buy

 

[passatgt]

Can someone help me tell which wire is the PWM on the 21.5" model?

 

[highvoltage12v]

Can someone help me tell which wire is the PWM on the 21.5" model?

From what I was told by Nick in a PM it's "pin 3 on the LED driver board, it's marked "Dim"" but please verify this yourself as I never had the opportunity to try this.
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It was my adapter. mDP adapter to DP on my Acer B286HK gives me full 4K@60Hz on my 27" 2011 with K1100M.

Yeah I found out way back when post #848 that 4k 60Hz output works. I was blown away then, and sometimes today I still connect my Samsung u24e590d to my iMac.

 

[passatgt]

From what I was told by Nick in a PM it's "pin 3 on the LED driver board, it's marked "Dim"" but please verify this yourself as I never had the opportunity to try this.

Thanks!

One more question Anyone here tried to use a raspberry pi to control PWM? Based on the docs, its working like this: https://sourceforge.net/p/raspberry-gpio-python/wiki/PWM/
I tried it with a simple LED and i was able to control the brightness. Any ideas what frequency should i use to test my iMac? (just want to make sure i don't cause any damage by accident). I created a small app that controls the raspberry pi and sets the duty cycle:

 

[Pascal Baillargeau]

Thanks!

One more question Anyone here tried to use a raspberry pi to control PWM? Based on the docs, its working like this: https://sourceforge.net/p/raspberry-gpio-python/wiki/PWM/
I tried it with a simple LED and i was able to control the brightness. Any ideas what frequency should i use to test my iMac? (just want to make sure i don't cause any damage by accident). I created a small app that controls the raspberry pi and sets the duty cycle:

View attachment 893836

13kHz. You find the info somewhere on this thread, between pages 70 and 120.

 

[passatgt]

13kHz. You find the info somewhere on this thread, between pages 70 and 120.

Thanks! I just tried it, and it works! Even works with 1khz, but i can see some flickering on the screen. But 13khz works fine. I will tidy up my code a little and i will post a guide to do this, its surprisingly easy to do. The benefit of this is that you don't need to populate an USB port, as it can be powered from an external source. You need to route out a single wire from the imac though, but i think its a good enough compromise.

 

[NOTNlCE]

Hey dude!

Did you try that?

Thank u!

Finally sitting down and reviewing my iMacs - both are on Mojave without Lilu.kext and WhateverGreen.kext and have native AirPlay support. Typing this on my AppleTV 4K from the iMac. I will see what I can do with Catalina over the next bit here.

 

[Jake F.]

Finally sitting down and reviewing my iMacs - both are on Mojave without Lilu.kext and WhateverGreen.kext and have native AirPlay support. Typing this on my AppleTV 4K from the iMac. I will see what I can do with Catalina over the next bit here.

Oh! I see... I tried it again and now it works! thank you!

BTW, what about the 'Sidecar' option? would it work too?

 

[NOTNlCE]

Oh! I see... I tried it again and now it works! thank you!

BTW, what about the 'Sidecar' option? would it work too?

Was just reading about that. If you have not done so already, can you use @highvoltage12v's provided patches to enable HEVC decoding on your machine? This, in combination with the sidecar patch? might be promising. Digging into the requirements a bit, it should be feasible unless the entire framework changed with Catalina for Sidecar support.

Currently building my Catalina patcher - left the speedy USBs at work, so the ol' 2.0 ones are taking a while. I'll test on my end as soon as the install finishes.

 

[SKYNET-1]

Hi
Its intéressant to know if the gtx 880m woks in imac 2011 27 even if no boot screen but if internal screen works its a good oportunity , to go fast because at the moment ther is no more wx7100 to buy

few on ebay for >$300... the 7100(= RX480) is plug n play like the kepler GPUs? whats missing? bootscreen? brightness adjust?

 

[HighSierraCosworth]

few on ebay for >$300... the 7100(= RX480) is plug n play like the kepler GPUs? whats missing? bootscreen? brightness adjust?

From the First Page of this thread

AMD WX7100
Recognized by macOS as a Radeon RX 580, can be flashed for boot screens alongside EEPROM. Requires hardware level backlight mod for internal LCD. With custom VBIOS, cannot load driver in Windows due to AMD VBIOS checksum issues resulting in an "Error 43."

 

[SKYNET-1]

From the First Page of this thread

AMD WX7100
Recognized by macOS as a Radeon RX 580, can be flashed for boot screens alongside EEPROM. Requires hardware level backlight mod for internal LCD. With custom VBIOS, cannot load driver in Windows due to AMD VBIOS checksum issues resulting in an "Error 43."

thx, ok... not work with win = fail for me so still the best/powerfullest option is the 880M, because only the bootscreen is missing, when i want a bootscreen too, the 780M...

n somebody tried to edit the bios rom from the mac itself?

n found this: https://forum.lowyat.net/topic/4175243/all
fake?