I'm working on my PC then suddenly it turned off. I re-opened it but it won't start. Its not new to me because this is the 2nd time that my PC turned off unexpectedly. But the difference is, on the first time I encountered this problem, I can still start my PC but immediately turns off. But now, my 2nd time, it's not starting anymore. The first time I encountered this problem, I replaced the PSU with a new one but with a same PSU that I'm using before. But then, after few weeks of using the new PSU, the same problem occur. Is it suggested that I replace my PSU with a better one or it is not a PSU problem this 2nd time around. This is my PC specs:
Check the amount of amperes you have on your 12V rail, the 12V wattage and total wattage is equally important, you'd need maybe 35a for that setup, with 2~5a for a safety margin. (I'm myself new to this and learnt it recently)
A 5670 only needs about 5 amps. One of my systems has an OC'd Q9550, 4 GB RAM, a GTX260 - a card that pull about 15 amps at load from the PSU, a Gigabyte EP45-UD3P motherboard, 3 hard drives and an optical, and a Soundblaster card all powered by a Corsair 750TX.
Running 3 instances of Prime95 to load the CPU and 3DMark06 to load the GPU, it
pulls 375 watts from the wall as measured by my Kill-a-Watt meter. Figuring 80%
PSU efficiency, the system pulls 300 watts from the PSU.
I estimate that your system will pull about 200 watts from your power supply. Your PSU has more than adequate capacity. It's the quality I am concerned about. Try to borrow a better PSU for testing.