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Hi, further to What GPU's are compatible with iMac 27" 2011?, I am wondering what people’s experience has been with replacing the trouble-prone AMD Radeon 6970M with another Apple version versus a repurposed Dell/Alienware version?
Does the Alienware version last any longer, or is the problem with the iMac’s thermal dynamics?
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Lets first deal with the Dell/Alienware GPU board. The firmware on the board is not compatible with your iMac. You would need to burn a new chip with the Apple firmware or have a way to over-write the current firmware.
As to why the GPU board fails:
Even the Dell and HP systems of the same age face the same failures! The solder joints tend to fail when the chip is thermally shocked This Is The Reason Why Graphics Cards Die - FlipChip Design - MicroBGA BGA. Newer GPU’s run cooler so this is less of an issue.
While you can get a better GPU board (one with more VRAM) which will run better. You really need to keep the system clean and every three to four years replace the thermal paste & pads.
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Thanks for the comprehensive reply Dan!
For some reason this particular GPU has a high failure rate, hence Apple’s recall program. I had mine replaced twice and the latest one just died. I’m considering the “bake” method to squeeze a few more months out of the machine until new iMacs are released.
But if there was any evidence the Dell/Alienware version lasted longer I’d probably invest in one. You can get them on eBay with the Apple firmware pre-flashed.
The original recall was a defective chip carrier (BGA solder was bad). But the real issue is the flip-chip solder joints failing from thermal shock from running heavy gaming which this chip was not designed to support. Apple also didn't do a very good job on the thermal paste and pads so the heat buildup had a harder time getting to the sink and then the dust build up over time messed the cooling.
As for a high failure rate I would disagree, Its only when you push the system beyond what it was designed to run will the board fail.
Think of it this way... A racehorse will run to its death if allowed, it's only when under the control of the jockey does the horse not kill them self by over doing it. Same issue here!
One of my clients had over 100 2011 iMac's we gave them lots of TLC and I think we had I think 5 that had a GPU failure. over the years (beyond the recall)
The Apple board is exactly the same with the Dell version other than the firmware.
It depends on the EEPROM Dell used if you can even reflash them. Better to burn a modified ROM to a virgin EEPROM with these cards so you can go back.
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Hello,
It is possible to replace the card with one of DELL MXM cards.
For a 27”, the best choice is the Quadro K2100m as it runs cooler than the Radeon 6970m with a lower TDP and equal performance.
Out of the box, you will get to macOS. But you will loose the bootscreen (can’t use the boot menu using the option key or access the recovery OS), no backlight controls and no target display mode.
However, there is good progress made on this.
This thread cover this well.https://forums.macrumors.com/threads/201...
I upgraded my iMac and running Catalina as the Quadro supports Metal. Quite happy so far.
As Dan mentioned, particularly in an iMac, dust and heat are the reason why the video cards are dying. I disagree that they are not designed to run intensive tasks. A GPU is design to run at 100% of its capacity when needed, especially without any overclocking, if it’s cooled properly. These machines were marketed by Apple for creative work not for word processing.
The issue with iMac is the thermal solution is well under performing for this type of GPU and the thermal paste Apple uses is really bad. My current Radeon 6770m is still working. However, after my warranty expired, I took down the CPU and GPU, repaste with thermal grizzly paste, undust the fans and I have been doing that every 18 months for the past 8 years. The recent upgrade to the K2100m was more to get Metal support and upgrade to Catalina. Also, websites are getting heavy and just browsing apple.com on the AMD card was getting choppy.
Cheers!
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@johnnyappleseed - My comment on using a Dell Radeon 6970m MXM board (apples to apples).
Sadly, rigging up a NVIDIA MXM board to gain Metal support will be short lived.
Apple will be ditching all NVIDIA drivers in the next macOS release. Apple also quietly stopped support CUDA with the release of macOS 10.14 Mojave. So while you can get basic graphics with the NVIDIA board it won't leverage the better functions.
'Creative work' can be anything between a writer to a video artist! When Apple started the design process of this system back in 2009 (yes way back then) it didn't realize the speed of change that was going to happen in software. Using apps back then were mostly light weight graphics just getting the GUI for writing and other basic spreadsheet and DB tasks. It didn't take long for heavy graphics gaming became a hot area with the introduction of Doom and MS Flight which gave realtime gaming environments.
I killed my iMac GPU four times! Apple hated me as I had it replaced every time under warranty except the last one (fifth) which I killed two years ago and now only use this system for writing! ;-}
Frankensteing systems is always an iffy proposition! I'm not against it its just a matter of what the person is able to do as well as the expectation. Most people here want simple fixes and they don't want to loose function to gain something. While you wanted to move to Catalina, many people can stay at Sierra or even High Sierra (an OS I don't like as its was an experiment forced onto people) and Mojave then forced people to move off of older non-metal GPU boards.
Well,
There is no evidence yet Apple will drop Nvidia driver in the next release until the 10.16 beta comes out in June.
I personally use a 21.5" 2011 and this machine was marketed alongside the release of Final Cut Pro X, which was built to use AMD GPU acceleration. And when it comes to heavy gaming, well, no Mac are built to run games.
That being said, my 6770m is still working since 2011 and I have been running all versions of X-Plane, played hours on Overwatch and finished GTA IV and V on it. Alongside heavy work on Final Cut and Motion. And for the record I live in Singapore. Average temperature is 31ºC (88ºF) all year long and this machine runs most of the time without AC.
I made the choice to go Frankenstein because for less than $100, I have a Mac that can run Catalina and the apps I need that were no longer supported on High Sierra. Catalina should be supported for probably a year or so after the 10.16 release so I should get at least 18 months out of it until I will really have to buy a new machine. Current iMac are just too old from a design perspective I prefer to wait. Can't stand these antique bezels.
@fabienpascal - I'm not against doing it, just be aware of its limitations!
The drums have been beating for over a year about NVIDIA being sent to the dog house! Apple never got reimbursed fully from NVIDIA on the failed GPU mess they had. Apple also didn't do their customers any favors either as they didn't get replacement GPU's for all of their customers so many just got patched boards vs rebuilt boards with a fresh GPU that came from a clean run.
@danj They also tried to troll Apple for royalties when they went to AMD. That sealed their fate for good at that point. As if that was a good idea when they screwed them on the reimbursements...
Makes me glad they replaced my 8600M GT Pro knowing they patched bum parts. Probably decided it was cheaper to can the laptop or they ran out of patched stock when my board was diagnosed under the 8600M GT mess.
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