Lately my Computer has been turning itself off at random intervals. No BSOD its like the power has been cut. I *think* i hear a 'click' sound whenever it happens. I can reboot immediately after and it might run on for hours.
This happens under load, when idle, at the login screen and it even happened once during start up.
Check the motherboard for scorch marks, blown transistors ect. Nothing.
Changed the Ram. No improvement.
Checked the heat sensor readings. Nothing running too hot.
Checked if all cables are correctly plugged in.
Did a SMART check on my HDD with Seedfan. Seems fine.
Logged the sensor readings with hwinfo.
It appears to happen more frequently when I'm putting some strain on the machine e.g. when I play Binding of Isaac. But since it also happens when I'm afk or browsing the web this might just be random.
From what I've read it's most likely the PSU (750w Delta Electronics)?
I think you're probably on to something with the PSU. If you're hearing an audible click like that preceding each shut down, there is a pretty good chance your power supply is dead. Or at least no longer up to snuff. Replace it with a quality brand, Seasonic, Corsair, etc.. and you should be fine.
A system with a single HD 4870 requires a 500W PSU with at least 34A on the 12V rails. Any decent 750W should be more than electrically sufficient for your system; actually overkill for your system. There are many more likely causes for these faults than the PSU at this point...let's see what BSOD error codes you're getting.
Alright, 5 min Binding of Isaac did the trick. The Comp powered off.
No BSOD (auto restart disabled).
I did check the event history the only errors i get are that the windows was not able to shut down properly.
I've been running my pc with part of the case removed I'm now certain that there is a 'click" when it powers off.
Thanks for all the constructive feedback so far. I just got a new PSU which as it's first deed completely fried the motherboard. The PC doesn't boot beyond the BIOS neither from HDD nor from CD.
I tried this with everything disconnected but the drive / hdd so it has to be the motherboard.
Since I installed the new PSU some leaking transistors have appeared as well which makes it even clearer.
But now I wonder if the new PSU might be defect (brand new corsair) or if the old one was simply not powerful enough to deliver the killing blow to my mobo . Or if this is just random... the PSU Voltage readings in BIOS at least are fine.
It sounds like the mobo was on its last leg and just jumped off the cliff...I don't think you have anything to worry about with the PSU. I would test the other components for stability if you use them in another system.