Asus p5k fails to turn power on

[colinwray]

Hello,
My p5k fails to switch the PSU on for a long time after mains is turned on. I have changes the PSU and the BIOS battery.

 

[clutchc]

I had a bad motherboard once that did that same thing. Replacing the board solved the problem.

 

[colinwray]

Gee thanks clutchc, I suppose that after 4.5 years I should be grateful. Can you recommend a current replacement ?

With everything disconnected except the CPU it now turns on and off for about 10 seconds at a time. It is definitely caused by the board grounding the power-on pin and then letting it float again, during which time the power ok pin is high and all the voltages are correct.

I can ground the power on pin to keep the psu on, but it doesn't then boot.

I am sure it is a simple fault, the system ran for 9 hours yesterday just fine, after the delayed start.

 

[clutchc]

If it indeed is the motherboard, finding a replacement LGA 775 board that you can use with your existing memory, CPU/HSF, etc. might be a bit of a challenge. Especially if you are using the x16, x16 SLI your old board provides.
Your board ( http://usa.asus.com/Motherboards/Intel_Socket_775/P5K/#specifications ) may only be available as a used item somewhere.
Here are some LGA 775 boards available at EBuyer if you're in the UK: http://www.ebuyer.com/search?page=1&store=2&cat=14&filtersubcat=658
And some LGA 775 boards available at Newegg if you are in the US: http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007627%20600007879&IsNodeId=1&bop=And&Order=RATING&PageSize=20
But be sure to verify they use DDR2 memory and not DDR3.

You may have better luck looking for a good used board someplace like eBay. I've always liked Asus, Gigabyte, and Asrock boards, myself.