Pinpointing the fault

[Mazzle]

Hey folks,

I've been having a torrid time trying to nail down which component has failed and after trying a few different things I wanted to throw this out there to see if you on you can find out where I'm going wrong. The background is that after many months of problem free use I went to sleep one night and upon waking up found that my T.V. and PC had been affected by what I'm assuming is a power surge from a heavy storm. My specs are:

MOB: Asus P867 Pro
CPU: Intel i5 2500K
RAM: Corsair 4GB 2x2 Sticks (CMX4GX3M2A1600C9)
GFX: EVGA Geforce GTX 560 Ti
PSU: Corsair TX 850

On trying to boot it refuses to POST and there are no beeps. The only error light is the DRAM LED being solid red indicating a problem. The CPU LED is off as is the VGA LED (CPU LED flashes once to indicate it's booted but it doesn't get as far as the VGA LED). The RAM has been replaced with two other sticks of the same model/make and with Corsair Vengeance 4GB (2x2GB) with the same problems. The motherboard is receiving power (green light on) however after trying to sort the problem out for a day the 560's fan stopped spinning up. I replaced it with a GTX 260 I had lying around and it does power the fan but still no boot.

I picked up a AsRock Z77 Pro4 in fear that the mobo had died (I was already on the second PCI Express slot of the Asus) and tried the components in that (mix of new, old and new/old). This however just boots up and resets infinitely with no POST or beeps again. It has onboard video so at least I have ruled out the GFX cards being the culprit.

So my question is, of the two components I haven't replaced is it the CPU or the PSU that is the problem? Any advice would be fantastic as I've lurked on the forums here for years and I've seen what you can all do!

Thanks!

[Willzzz]

You can't borrow a PSU from a friend?

[Mazzle]

Unfortunately no. A last resort will be to take it into a PC repair shop for a free M.O.T. (found a place already) but that's time I don't want to waste if I can diagnose myself and get the part ordered within 24 hours.

[Daheelah]

Hi, This is not a solution, but it might help with your efforts to isolate the offending component(s). I have an old machine that began exhibiting similar symptoms a few months ago. I have yet to do a full diagnostic though as I really plan to re-use the case only for a new build. This might not work for you, but to attain boot, I toggle between complete power off (at wall socket) and the reset button. After three or so cycles, it boots up and then I have the option to use last know configuration to boot into windows. This of course is NOT a solution, but if you can successfully boot up, you have the option of diagnosing from within windows.