Bit of a long story...
Just moved my parent's pc to a better case that actually has airflow(old std beige case didn't even have any fans apart from CPU). their pc kept crashing(5-6 reboots on 1st startup to get to windows). I wanted to do a fresh install of XP but thought I'd upgrade at the same time.
Due to my recent upgrade, was going to put my old kit in their pc(which they only use for web browsing and email etc). I had an AMD64 3000+ on a K8V board. this all worked fine before I upgraded my pc. When I built this into a new case I'd got for them(jeantech Phoong 2), it powered up but would not give me a display,after checking all connections(including 4 pin power lead)swapped the agp card I had in there(gigabyte 7600) for another one(msi 6800gt), same thing. Played about with swapping ram and everything else round and no joy.
Decided to use their old parts(NF7s board with an XP2200 cpu) and it booted fine(this was done outside the case to check it worked first). I then took their heatsink off(thermaltake typhoon) and took it apart to get rid of the large amounts of dust it had accumulated over time and put some new arctic silver on it. Put it all together but with my DDR400 ram and the gigabyte board from my other pc.
It booted but with 1 big problem - the post screen and bios took ages(2-3 mins) to load as the test on screen was coming up as if someone was typing it and in the bios it was drawing every line on the screen. the CPU was also showing as a XP1350 and not the 2200 that was actually in there(when I did the original test it came up correctly)
I cleared the cmos again(after removing the new cmos battery I had installed) and same thing. Tried swapping ram for the old ram and again same thing.
I'd read on another post somewhere that it could be the cpu throttling if the heatsink wasn't installed properly. I took the heatsink off, checked it and reinstalled it but nothing changed.
Now run out of ideas and need help, I've changed everything I can think of, reset the cmos numerous times, changed the cmos battery but nothing will help.