Man I had hoped it was something simple like the fan profile was not kicking in. Darn, nothing is easy yeah.
OK I will pull out my Matrix and have a play around and see if I have anything similar. Temps are a bit lower here but the delta should be the same.
Thanks mate.
update: Voltage on my card is the same as yours.
CPU Voltages (nV) 1088
OEX,VDD (mV) 1059
Memory Voltage (mV) 1580
How does that compare with your card?
My temps are 26'c idle and my max during a stress test looped was 54'c and my fan cycle did not budge from 20%.
Looking at the other temps my card was about 30'c cooler than your on the PCB.
One thing that I noticed and is maybe interesting for your problems the reason why your clocks do not seem to revert to the 2D settings? After a few seconds of not being used (stressed) my graphic card reverts to the second 3D 400MHz mode and then down clocks to 50MHz and the default 2D clocks.
Could you have a look and see how long it takes before your card down clocks to 2D settings please.
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