I hope this doesn't count as necro-ing a thread (last post was in October), but it's the one closest to my situation.
I have the following setup:
- MSI 970a-g43 motherboard
- AMD FX-6300 cpu
- ATI Radeon HD 4550 graphics card
- 4x 2GB RAM sticks
- 2x 500 GB 3.5" SATA hard drives
- CoolMax 700W psu
- 16x r/rw DVD burner
- cheapo SD and others card reader that fits in the floppy drive bay
- Older PC tower that has a temperature sensor built into it
I built it around November 15th, and it worked until a couple days ago (December 12th I think), when it started doing the sudden shut-off thing. Same as Adresch described: shuts off, tower light blinks, have to flip the i/o switch off and back on to boot again. I consulted a friend for some suggestions, and he said I should put a water cooler in there, because the stock heatsink that comes with most processors are junk. So I went out and bought a Corsair H55 water cooler and installed that.
The computer seemed to run for a bit longer before shutting off. I loaded up the BIOS software, SpeedFan, and HWMonitor. SF said the CPU was running average of 48*C, and GPU was averaging 51*C. The CPU's highest was at 61*C and its lowest was 36*C. BIOS software said CPU was at 35*C the whole time. HWMonitor listed the GPU at 51*C, and the CPU at 7*C. These are all very inconsistent with each other as far as I can tell, so I don't know what to make of these readings. Didn't seem to much matter as the computer continued shutting off.
My options then being replacing the PSU or the motherboard, I decided to replace the power supply, since I was just within the 30 days. Switched for a ThermalTake TR2 700W. Before installing it, I pulled the tower's CPU temperature sensor wire from between the water cooler heatsink and the CPU, just in case. Then I installed the PSU, checked and rechecked all of the connections, and turned it on.
I then spent the next two hours rechecking everything, even unplugging everything and putting it back together. Still nothing. The best I could get was a flicker of the tower light and the fans doing a quarter turn before ceasing movement. The red LED on the front of the SD card reader stayed on the entire time, though, so I guess it was getting at least a trickle of power. I also removed everything but the PSU, motherboard, CPU, and one stick of RAM. Still no power. I think the new PSU may have been open box, so I'm returning it today for a different one, and even bumping it up to 850W.
I'm not sure that will solve my original issue though, so I'll be looking for a heatsink to put on the VRMS as mentioned. Just thought I'd get this down in a relevant thread in case anyone had other thoughts on what could be going on.