For a little over a week, I borrowed my friend's 4870. Naturally, I had to take out my 3850.
Just tonight I returned the card to its rightful owner and placed my old and trusty 3850 back. However, as I did, after reinstalling CCC, it started crashing. And crashing. And crashing. I thought it was just a bad install so I installed CCC and display drivers again. However it kept on returning.
Suddenly it struck me that it was the ATI Overdrive that was messing things up. I don't know how but I think the settings that remained where the Overdrive settings I used in the 4870. So I turned it off and restarted without an OC to the card. It was fine. But I thought, hey I should just put it to my old settings, which where 740 MHz and 999 MHz for core and memory clocks, respectively. However, when I did that, the crashing thing went back again.
I can't really pinpoint the problem, hopefully it's not hardware-related. Any ideas on what's wrong? I'm running it in stock clocks again but the extra 5 fps I get with it OCed helps since it' starting to struggle because of age.
I doubt it's the aging because it never ever froze on me before this, and then suddenly it freezes nonstop.
About the thermal paste, do I just need to use it for a while to get it running optimally again?
Thermal paste is the compound that secures heat transfer from the GPU to the cooler. You would have to remove the cooler clean both and put back together with new paste. Before you do that check if you have any dust and lint in the cooler and clean it out as a first step to see if that changes anything.