Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

27 iMac 2011 Graphics card upgrade 6990m

A

All Taken

macrumors 6502a
Original poster
Dec 28, 2009
790
13
UK
I'm looking to upgrade my 27" 2011 i5 6770m 512mb to a 6970m 2GB. This is entirely possible with the available Apple service part but I was thinking and would really love a detailed answer.

Could I install a 6990m? I'm aware Apple don't supply a iMac with this card but i'm pretty sure I read somewhere that Lion has support for all Radeon 6 series cards (could be wrong) If it does support it without EFI flashing then great. If not could I perhaps use a flash from a 6990 desktop possibly Mac Pro card that somebody has done on here???

Really need some intelligent answers on this, not the usual 'You should have purchased the higher model anyway', 'You can't upgrade the graphics' and Seems like a lot of work for not much gain.

Thank you.
 
Last edited:
I guess something that needs considering is whether or not the mobile gpu used currently in the 27" is the same form factor of 6990m's found in PC laptops. But when I say same form factor I'm also referring to whether or not the heat sinks found on Apple's 6970m would be compatible to attach to a 6990m. Then power requirements and TDP needed, as well as the drivers, ect., all need to be thought about.

Otherwise beyond removing your existing card, inserting a 6990m with Apple's heat sink, connecting a thermal sensor, it's all set - almost plug and play if heat/power/drivers/form factor all work in your favor
 
Well, 6990M is an underclocked Radeon 6870 and 6970M is an underclocked Radeon 6850. The only difference between the cards is the number of shader cores. No idea if the number of cores is hard-coded in the driver. There is a possibility that the card will work nicely as it is, or maybe with an injector. Netkas reports that OS X drivers seem to natively work with the 6870. By no means should you flash that card with the desktop's 6990 firmware, you will surely destroy it!

So, if you are rich, than get the card,put it in and see whether the system boots. It might ;)
 
leman said:
Well, 6990M is an underclocked Radeon 6870 and 6970M is an underclocked Radeon 6850. The only difference between the cards is the number of shader cores. No idea if the number of cores is hard-coded in the driver. There is a possibility that the card will work nicely as it is, or maybe with an injector. Netkas reports that OS X drivers seem to natively work with the 6870. By no means should you flash that card with the desktop's 6990 firmware, you will surely destroy it!

So, if you are rich, than get the card,put it in and see whether the system boots. It might ;)
Click to expand...

Tempted, so tempted. Seems like a lot of work for not much gain though.
 
All Taken said:
Tempted, so tempted. Seems like a lot of work for not much gain though.
Click to expand...

I thought you considered that a pointless reply :p

P.S. BTW, another things which is probably more important is the cooling system consideration. The iMac is already designed on the limit of thermal engineering. There is a good chance that a more powerful GPU could send your whole system smoking...
 
leman said:
I thought you considered that a pointless reply :p

P.S. BTW, another things which is probably more important is the cooling system consideration. The iMac is already designed on the limit of thermal engineering. There is a good chance that a more powerful GPU could send your whole system smoking...
Click to expand...

:p I considered this as i'm stuck at the thermal barrier first before anything else matters. I would say the card is thermally acceptable to the heat sinks and surrounding tech. My logic is that Alienware laptops contain this card and have much more surrounding constriction, less airflow, and smaller heatsinks.

Apple have been releasing faster cards with perhaps a higher heat to power ratio at iMac refresh but the design remains the same. Would anyone with Mac Pro experience care to weigh in on compatibility here?
 
Aluminum iMacs actually have very good cooling. They always feel hot because their bodies are designed to act as a giant passive heatsink. Plus it has three fans that usually only idle. The fans can an do rev up if heat becomes a consern, but it rarely does. Apple's other iMacs from the G4 to the white Intell had a much lower heat tolerance, with the G5 having known overheating problems.
 
Intell said:
Aluminum iMacs actually have very good cooling. They always feel hot because their bodies are designed to act as a giant passive heatsink. Plus it has three fans that usually only idle. The fans can an do rev up if heat becomes a consern, but it rarely does. Apple's other iMacs from the G4 to the white Intell had a much lower heat tolerance, with the G5 having known overheating problems.
Click to expand...

Exactly my thinking, my guess is Apple will introduce a hotter card at the coming refresh but the fan, heatsink placement and case design will remain the same.

Any thoughts to compatibility?
 
Eugen Mezei said:
Bump
Any progress in this question in all these years?
Click to expand...

A better solution has been made. Better enough to drop this approach.

forums.macrumors.com

2011 iMac Graphics Card Upgrade

iMac 2009 to 2011 MXM3 graphics card upgrade (Lastest update 10/13/2023 - this is the official documentation page - you found it finally!) This is the single and only documentation post. During the last years we constantly updated this post to reflect the lastet development of vBIOS and OCLP...
forums.macrumors.com forums.macrumors.com
 
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back