This problem occurs at different times. And again it never produces a BSOD, event log or dump and the fan ALWAYS then goes full blast. Sometimes it happens while in the middle of something, sometimes when the computer is idle. Have to hard reboot it then but usually it will then occur on reboot, freezing anywhere from the Windows logo to sometimes shortly after desktop icons appear. Could take me multiple boot attempts before it finally makes it into Windows and sometimes I can run it for a while sometimes for few hours before it locks up again, sometimes not.
Thought it was a heat issue but running monitoring software showed the CPU heat levels consistently remained in safe range 40-60c, even moments before freeze up. Still blew out of the fan area just in case. Also applied fresh thermal paste. However alot of time it happens when the computer has been off for a while, even overnight and I first turn it on. Even in sleep mode when I wake it although in that scenario the screen stays black although the lights come on and the fan goes full speed as before. In these scenarios the machine is obviously cold so can't be overheating that is triggering it.
Thankfully the machine has cooperated enough times that I have managed to run Burn In Test inside Window (Passed), Memtest86 outside Windows (4 passes, no errors) and even S&M Stress inside Windows which I ran to completion like 6 times in which it passed 4 of them. The other 2 times it did freeze (again fan full speed, screen frozen) during testing but I think it was just one of its random freezes rather than being specifically triggered by S&M's tests. Also it passes the Dell preboot assessment. Updated BIOS to latest version as well.
Went ahead and did a clean install of Windows 7 with latest device device drivers but problems persisted. Resorted to trying clean install of Windows 10 with latest device drivers but problem remains. Amazingly enough I was able to get thru both reinstalls with no freezup issues which I found odd. Resorted to clean install of Ubuntu just to see what would happen and amazingly it has been stable for about 24 hours but since the problem seems to be hardware related rather than OS and driver related, installing Ubuntu should have shown the same stability issues.
I think I have exhausted all other causes so my thoughts are its either a bad processor or a motherboard issue but before I invest in a new board or processor I wanted some opinions.
Edited by amn70, 19 May 2016 - 12:42 PM.