PC shutsdown after 2-3 seconds during boot.

Exactly the same problem happens with me also. I cleaned the CPU fan, as lot of dirt get stick between the heat sink causing ultimately to overheating. At last, when the fan becomes dry, I put it back there and my problem get solved. Hope this helps!!

Hi UKMedia, Well where to start here, this could be a number of things causing the problem. The first thing I would try is a visual inspection of the PSU inside but this is not a job for the feint of heart as it can cause deadly electric shock if handled incorrectly. What I would look for is dead capacitors on the PSU (especially if its older than 3 years). A dead capacitor will have a slight budge on the top where the vent is and may even burst open altogether. Google dead capacitors first if your not familiar with what they look like.

If you don't want to try that, you could use a multimeter to test the PSU by removing it from the system and shorting the appropriate pins in the 24 pin connector. This will turn it on and allow you to use the probes of the multimeter to test each of the pins voltage readings. Again Google will give you a full guide on testing a PSU with a multimeter - be very careful not to short the wrong pins!

I have had a little look at the specs your running and I can't say I have ever heard of that brand of PSU. What I would say is that if it is dead caps, just replace the PSU with a decent branded alternative rather than replacing the CAPs as this will ensure the problem doesn't return to bite you in the ass in a few months time.

If it's not the PSU then it may be a faulty motherboard or a problem with the BIOS but because of what you have described I would wager it being a problem with the PSU itself. Just out of interest how old is the PSU and how much did it cost you?

Thanks both

I've reset the BIOS by clearing the CMOS, checked the MB (it's only 6 months old) and can't see any problems. Cleared any dust and removed all ancillary components and memory - still no change.

I have a replacement PSU (The old one cost about £300 and is about 3 years old) on order. If this doesn't fix it, I've spoken to the MB retailer and will replace the MB bundle.

I'll let you know progress....

Regards
UK Media

Wow that's an expensive PSU. Fingers crossed for you!

Layback Bear said:

UKMedia good call on the power supply. That would of been my first move if it was my computer.

What new power supply have you selected?

Hi Layback Bear

I went for a Dark Power Pro 10 - 1200 W in the end.

All changed now and booting, although it has cycled once in the 5 reboots so far so I don't think it is really fixed yet. I'll monitor over the next few days.

Regards
UKMedia

Well as of 10 Feb 2015, no problems booting. It looks like it was the PSU...

Great news, let's hope that's an end to your problem!