Nice work!!
The power control problem with Afterburner and newer Nvidia drivers is happening to other users too, apparently the developer is Russian and has been unpaid from MSI for over a year, so Afterburner is not being updated to work with latest driver updates...
If you send me the vbios that came with your card I can take a look at the power settings, I've seen some mxm HP cards with vbios TDP up to 190W. I won't be able to change power settings but maybe can find a compatible vbios with lower TDP.
Also, take a look in GPU-Z to the sensors tab, while running some benchmark like Furmark, that will show you TDP and PerfCap reason. That may give clues to what is happening above 70% power.
So, just to update on the rtx 5000 that I installed in my imac 2011.
I have got it working stably, but not with the full performance. As I mentioned earlier I have to limit the power to 70% using afterburner as the display will occasionally freeze when the GPU is working hard at anything over the 70% value.
The performance is still very good and my son can play games, but I want to look at it again as I am sure that the card could be set up to perform much better in the imac.
M0bil helped me by checking the logs and established the following:
'sometimes the card seems to be reaching much higher gpu clocks than the one set as max on the vbios (1350 MHZ), if you look at the log sometimes clock jumps to 1845 MHz, voltage to 0.9430v and the PerfCap vRel is shown.' - That is when the screen freezes
I tried flashing a different bios from techpowerup. The original version was:
vbios, it is version 90.04.4F.00.11, device 10DE:1EB5, build date 01/31/19 for board id 0x00EB
I tried this one:
https://www.techpowerup.com/vgabios/229124/229124
It caused the display to go black and I had to re-flash to the old bios using remote desktop to get the display to come back on.
One interesting thing is that when I type NVIDIA-smi -q -d CLOCK
The result shows max clocks
Graphics :2100
Sm: 2100
Memory: 6001
Video: 1950 mhz
So I'm wondering if anyone has any suggestions of how I can limit the card from increasing the clock so high occasionally so that I can get more even and better performance more of the time.
Also, is there any potential benefit in down grading the CPU from the current Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz to a lower power one? Would that leave more power available for the GPU or is total power consumption not the important factor here?
Any other ideas of how to improve the stability.