Zipp, I've since posting run a diagnostic tool on both the RAM and HD, neither showed up any errors. (I'm assuming if it was power it'd be failing on something obvious?)

Sharon, thanks. I'm trying to install with an original XP, I don't have anything else.
I'm going to take it to a man who has a much knowledge than me.. I'll suggest that to him.

I've found many posts commenting on how difficult the motherboard can be to use with pratically exactly the same problem,which is slightly reassuring. However, their remedies haven't worked for me.

I'll see what happens with the guy, I'll post back with a resolution if found.. for the archives