Motherboard culprit for unexpected shutdowns?

lipusal

Honorable
Apr 14, 2013
15
0
10,520
Hi everybody, I posted this under Motherboards because I think it the only possible culprit for my build's sudden shut-downs. It's a Biostar TZ77B.
Shut-downs occur in the least expected of times, generally under stress (games) but also on idle, and even while in the BIOS or while running Win 7's memtest (I remember having run it before and it completed with no errors). I can always start the computer again but the less I wait between reboots, the less time the computer manages to remain on.

So far I have:
-Formatted all my drives (1 SSD where the OS is installed and 2 HDDs) and started fresh two times now
-Changed the power supply (OCZ 600W to Thermaltake 430W)
-Changed my graphics card (from Radeon HD 6670 to Nvidia GTX650)
-Moved my two RAM sticks to different slots
-Changed the layout of fans to optimize air flow
-Checked temp on my CPU (Intel Core i5-3550 Ivy Bridge) and according to HWMonitor there's no temp over 60C
-Attempted to update BIOS (latest version already)
-Attempted to update SSD firmware (renders Windows unbootable, needs the repair disc to fix)

As of right now my computer is sitting on a fresh Win 7 install but I can't do anything useful before it turns off. I'm starting to get desperate. Any help is appreciated!!!
Thanks!
 

lipusal

Honorable
Apr 14, 2013
15
0
10,520


Thanks for your reply! I hadn't messed with the CPU yet but surprisingly all 4 of the fan's legs were slightly off. I put everything back in place and so far it hasn't shut down. Can't believe the solution is this simple after so much trouble! I'll mark this as solution if this behavior continues.
 

lipusal

Honorable
Apr 14, 2013
15
0
10,520
No such luck, I'm afraid. Symptoms still persist. Last I checked after fixing the fan, CPU temps weren't above mid-50's. I have taken out the graphics card but it doesn't help. Any other suggestions?
 

lipusal

Honorable
Apr 14, 2013
15
0
10,520


I will try that later, but for now I reset the CMOS following my mb's instruction manual (shorting two jumpers) and the computer seems to have stabilized. I'll continue doing tests. Could this have been the solution?