As per title. All worked fine yesterday, went to turn on this morning, it came on before turning off. Not come back on since.I know it is in a similar category as needles in heystacks, but what pieces of hardware can be ruled out? I guess it can't be the GPU or Hard drive. Perhaps the PSU?It is an OCZ 750W 80 plus bronze modelCPU is an i5 2500k at 4.5ghz, 1.38 vcoreGigabyte Z68 moboSeriously pulling hair out

Tried resetting your CMOS already?

I domn't know how to do that. What i have done is took for e.g 1 memory module out, plugged the power cable back in and tried to turn on. The GPU, CPU and rear fans all spin for about 0.5 second, and then stop. So there is power from the wall to the PSU, but non getting from the PSU to the components?EDIT: i located my CMOS reset pins. Usually there are 3 pins with a jumper on pin 1+2. But this MOBO only has 2 pins and no jumper. So i unplugged my power cord, and connected the 2 pins for about 6 seconds. Plugged the cord back in, pressed the power switch and again the fans span for 0.5 seconds before stopping.

Weird.Is this your board? http://europe.asrock.com/downloadsite/manual/Z68%20Pro3.pdfPage 29, seems to be a conventional 3 pin jumper

No, that is the one i wanted but was out of stock.Mine is a GIGABYTE Z68AP-D3EDIT: just plugged in an old 500W PSU (I know not powerful enough to sustain power) and it actually turned on. Blue lights stayed on and cpu fan did begin to spin, before stopping. The PC was on at all times however.How on earth can a £80 PSU fail, after 1 week!EDIT 2: The CPU fan hadn't stopped, it slowed and then began properly.. It boots up now, BIOS are at default and it loads up. I don't want to run it for long as its only on 500W, but does that point to PSU failure?

No, that is the one i wanted but was out of stock.Mine is a GIGABYTE Z68AP-D3EDIT: just plugged in an old 500W PSU (I know not powerful enough to sustain power) and it actually turned on. Blue lights stayed on and cpu fan did begin to spin, before stopping. The PC was on at all times however.How on earth can a £80 PSU fail, after 1 week!

Oh, sorry, I focused on your signature instead of your original postA 500W PSU should be plenty to power on that system. Does it get to post?

I cant install my HDD because the 500w PSU doesn't have SATA connectors, only IDE. So it allows me to go in to my BIOS, and if left to just boot up, it gets to the 'OS failed to load' which suggests if the HDD was installed, it would boot correctly.

Yes, it is your PSU.

IDE connectors! was this a new PSU?

I cant install my HDD because the 500w PSU doesn't have SATA connectors, only IDE. So it allows me to go in to my BIOS, and if left to just boot up, it gets to the 'OS failed to load' which suggests if the HDD was installed, it would boot correctly.

Ok, so it posts. Looks like it's the PSU obviously. If you want to be sure the CPU, GPU and RAM are ok, you could use another computer to create a bootable USB drive (or a CD) with a Linux OSNow that you can enter the BIOS, did it actually reset the OC to stock clocks?

Yes, BIOS are defaults now. I called Overclockers, who have given my a returns address, so i'll put it in the post now for them to test. I'll end up with a new one, but who's to say that won't die. It wasn't as though it was old, it was brand new.And the 500w PSU i used was IDE, yes that was old!

Yes, BIOS are defaults now. I called Overclockers, who have given my a returns address, so i'll put it in the post now for them to test. I'll end up with a new one, but who's to say that won't die. It wasn't as though it was old, it was brand new.And the 500w PSU i used was IDE, yes that was old!

Just bad luck. It was a good PSU. If you can & want to go with a different PSU, try a Corsair TX650, or GS600. You don't really need 750W for that setup

I confirmed i wanted a replacement rather than refund, when i was on the phone to OC.Out of interest, there is nothing CPU/MOBO/HDD/RAM related that could have caused my PSU to fail? or is it just bad luck that maybe a piece of solder has come loose or something similar?

How good is the AC supply there? are surges a common ocurrence? I highly doubt any other part in your rig is to blame for that

... Out of interest, there is nothing CPU/MOBO/HDD/RAM related that could have caused my PSU to fail? or is it just bad luck that maybe a piece of solder has come loose or something similar?

Yes, in regards to the bad luck. It's happened to me as well. Brand new PSU lasts a short time and I have to go back and replace it. (Actually, I returned it and got a different brand and more powerful unit, just to be safe.)