Two Christmas' ago I built a PC for my brother-in-law using Asus P5B mobo and E6400 cpu along with GF7950 graphics card.

Had to look at it today and think mobo is on the way out - cpu also seemed rather pushed when playing Brothers in Arms game (peaking 85%) - graphics card ok but also a bit dated now.

So, question is should I get him a new mobo to replace the Asus or push the boat out a bit and rebuild his rig from scratch as an early crimbo present?

If I rebuild then I'm not sure re. socket 775 or 1156 (with i5 750)

Depends how much you want to spend, you could add a secondhand Quad Core and a newer GFX card for £150 or so that would really make it better.

If the memory is good it may be worth selling as premium DDR2 has shot up in value recently

a 4870/5750 is about £100 so a fairly cheap upgrade for performance and a quad core can be had around £100 and a decent motherboard from £70ish to overclock it if needed if you go 45nm on the Core 2 Duo/Quad side of things

The P5B is an ok mobo, is it the Deluxe ? Not sure if you could use a 45nm CPU in it, maybe with the very latest Bios updates as the P965 does support them in some circumstances.

Might have a little browse on ebay for some parts and stick with socket 775 so only need new mobo and a graphics card so a bit cheaper!

The Asus is the straight P5B and, as I said in my post, I think it's on its way out as has lost its bios settings a few times despite replacing the on-board battery.