Computer shutting down, no bluescreen, no overheat?

Demoliter987

Honorable
Oct 20, 2013
5
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10,510
So I built a computer for my gfs little brother about 2 months ago for his bday (his parents paid I did the work).
The kid is a gamer, and I wanted to get him something that'll do well.
Anyways, as of 4 days ago, the computer randomly froze up while he was on youtube, and shut down.
It wouldnt turn on for the next day, then the day after that, I came over and hit the switch and it came right on and ran all day without any overheating or visible issues at all.
Have no clue what could be causing this, anyone got some ideas?
Thank you very much for whatever help you can provide!

Oh btw, the temps are all sitting around 30-35. Under load its about 40-45 I'd say.
 

Demoliter987

Honorable
Oct 20, 2013
5
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10,510
AMD Athlon II X4 640 3.0GHz Quad-Core - cpu
Gigabyte GA-78LMT-S2P Micro ATX AM3+ -motherboard
Mushkin Silverline 4GB (2 x 2GB) DDR3-1333 -ram
Seagate Barracuda 500GB 3.5" 7200RPM - hdd
PNY GeForce GTX 660 2GB -gpu
Thermaltake VL80001W2Z ATX Mid Tower - case
Cooler Master R4-L2S-122B-GP 39.8 CFM 120mm -fans
Corsair 430W ATX12V - Psu
Lite-On iHAS124-04 DVD/CD Writer - optical drive
Microsoft Windows 8 (OEM) (64-bit) - OS
 

Demoliter987

Honorable
Oct 20, 2013
5
0
10,510


I'll have to look at that, at worst least Psus are decently cheap. But its gonna be a bit before I can get to the computer again. If any other ideas come up, please post um so I got a few things I can try before going out and purchasing one.
 

clutchc

Titan
Ambassador
Yes, the GTX 660 is a 140W card maxed out. That relates to almost 12 amps on the +12V rail. The Athlon II X4 640 is another 95W (8 amps). Add to that the MB's +12V draw and the drives, fans, etc that run off the same rail, and your PSU's 32A (+12V rail) may be marginal. Any overclocking will also raise the amperage draw from the rail.

Another thing to consider is the air flow that the PSU (and the rest of the system) gets. If it is sitting on a carpeted floor, be sure to set the PC on a board or something so as not to choke off air flow to the PSU. And check to see that the inside of the case is free of dust and that cables aren't blocking air flow.