PC won't post after CPU upgrade

[Random_guy]

Hi all,

So I swapped out my old E6750 for a second hand Q9400. Just finished installing it, plugged everything back in, and the PC won't post.

All the fans spin up, including the CPU fan, it gets the point where it would normally 'beep', and instead all of the fans power down. After about a second, all the fans spin up again and it repeats this process of spinning up then powering down indefinitely.

Any thoughts? Obviously I will swap the old CPU back in to see if it starts, but I'd like to know if there is anything else I should try first?

The board is a Asus P5k-VM if that helps.

[GoNz0]

what you said, check the socket for bent bins while your there, a close up with a digi cam can often assist the hunt for the bent pin.

[Random_guy]

Ok, will get on with that then. Just realised that I didn't reset the CMOS. Could this be causing it, or is it more likely to be a bad CPU/ bent pin?

[Iron Sights]

In case you havent already you might want to update the bios to the latest version

[Random_guy]

Digital photograph doesn't show up any bent pins. Reinstalling the old CPU now. Assuming this works, what's left to try with the new CPU? Updating the BIOS to the latest version, anything else?

What I mean is, at what point should I conclude that the CPU is a dud and start the process of trying to get my money back through ebay?

[iCraig]

Its a supported chip, so you probably just need a the latest BIOS.

Asus' website says you need version 0902 for the Q9400.

[Random_guy]

That's a fair, I'd forgotten that it might not be supported in the BIOS I have. Right, it booted first time with old CPU, I've flashed the BIOS to the latest stable version that supports the new CPU. Now to have another go at installing the new CPU. At least I'm getting good with Push-pins!

Is it likely to be the BIOS that's the trouble? I would have thought I'd at least get an error message with an unsupported CPU, rather than simply refusing to boot...

[GoNz0]

they can't predict the future so there is no guarantee to get a unsupported cpu error

[Random_guy]

Fair enough. Well that seems to have solved the problem, new CPU posted no problem and booted into Windows without a hitch.

Thanks for all your help guys.