My computer mysteriously shut itself down with no warning a few times over the past 24 hours, both at times when it was not being used but left on (incl. overnight) and a couple times when playing a game, so under at least moderate load.
This led to me installing a temp gauge (Realtemp 3.7) and a stress tester (prime95). The first run of the stress test showed a between-test phase idle temp of 79C but quickly pushed the cores to 105C at which point I stopped the test.
Then I opened up the tower and did a pretty thorough compressed air cleaning and made sure all the fans were spinning.
Oddly, all subsequent tests I ran didn't push the temp beyond 80C, and averaged around 40C. And for the next few hours, temperatures were just fine, including during gaming. Then just minutes after I left the computer alone, the fans kicked into high gear and when I checked the temp it was climbing over 90. I've copied a couple pieces of the log to illustrate (the temp's are in C; the far right column is CPU load %.
Here, while gaming:
19:56:15 3372.37 36 30 40 36 46.7
19:56:30 3342.44 36 33 40 39 53.1
19:56:45 3342.43 36 31 43 35 54.0
19:57:00 3332.46 37 34 41 39 60.2
And then later, just after stopping using the computer:
22:57:15 1596.39 87 86 87 89 3.2
22:57:30 1596.39 92 92 92 92 3.6
22:57:45 1596.39 88 88 89 89 3.4
22:58:00 1596.39 95 95 95 95 3.9
It seems like there's an obvious discongruity between load % and the CPU core temps. Could my cooling system just be sporadically failing?
Basic specs: Intel Core i5 3450 Quad 3.1 GHZ, 8gb DDR3, AMD Radeon HD 6850, CoolIT ECO A.L.C water cooling.
Thanks!