Now and then, both when gaming and normal usage the Radeon HD 6870 graphics card fan suddenly starts spinning at full speed and sometimes it causes instant shutdown of the computer, last time it happened I checked the temps with hwmonitor and it sense 95 degrees celsius and just before it was 34 degrees and about same just after again, also feeled and the GPU was not hot, not even warm.
I got a Corsair GS 600W PSU which is about half a year old, power supply shouldn't be a problem and the rest of system is prime95 stable, can I be relatively sure that it's the GPU and a new one later on would fix it?
It's not correct value, it's only showing those crazy values while it's going nuts, I can touch the fan with a finger and things are usually normal again, including temperature, sensor seems broken or something...
It can also like recently show negative temperatures, just detected -158 degrees celsius (-254 F) and pressing on the fan until it stopped behaving like a jet engine and temp was back to normal along with fan speed.
Broken thermal diode and there is no telling what else is wrong. The card could have gotten hot at one point then started failing. I've seen a few stories have ati/amd cards going bad out of the blue before but this one is new and it is odd that I seen another 6870 one eBay that had a similar problem then dropped dead at stock clocks.