My Computer hangs just before the Window's XP screen when switched on from cold. Reset or switch on when warm works OK.
In Safe mode the hang is immediately after loading MUP.SYS (long known issues with many threads) but it isn't this because press restart and it fires up fine. It even works OK if I press reset during POST when booting form cold.

I have tried stripping out BIOS settings to bare essentials and checked drivers, currancy of Bios, etc. etc.

I suspect that it is the PSU - anyone confirm for sure this is the problem? Current PSU is 300w and worked fine with machine for two years. its 1600 Athlon, 2 HD (40&80) DVD writer CD Writer. Also has five USB connections.

Ideas pleeeeeease.