PC Switching Off

[A[L]C]

Hi all,

My pc keeps randomly powering off. It just totally cuts out. It will switch on fine afterwards. Could it be my psu?

Ive only got a cheap one which came with my asus case.

If so, which one should I get? As cheap as possible.

Im running

A64 3000+
2 x 250gb hdds
x800gto2 gfx
and lots of usb devices.

Thanks