I'm having a weird problem with XP, just built a new machine, installed XP Pro, service pack new drivers etc. everything working fine. The next morning I switch on the pc it goes through the POST then just where you would expect the XP logo it just freezes. Heres the weird part if I then reset or power off the pc it will then boot up fine after that, I can reboot as many times as I want and it will boot up fine, leave it for a few hours switched off though and it will freeze again but only for that first boot up ??????? I've tried a few things like reinstalling XP, booting with just the hard disk connected (no CDROMS), removed the PCI cards set the BIOS to defaults but I always get the same result. Anyone have any ideas???

Maybe you've got a dodgy connection between the IDE cable and the Disk and/or board? It sounds daft but perhaps when the PC starts to warm up, the pins may make a full connection where they didn't before?

Yes, I agree these problems are generally cabling issues. I would certainly do a once over inside the box and make sure everything is snug and in place.