Richard many thanks for the reply,
The computer in question is made by Advent, around 3 years old and the spec as far as I know as follows,
Pentium 111 500 Mhz chip
Aopen MX6B motherboard
Aopen PA3020 graphic card
Windows Me
D drive is a DVD/CDRom
E drive is a CDRomRW
no idea about the power supply
due to the problem a full format was carried out a couple of days ago, with the problem then reappearing with one or other of the programs mentioned installed.
Many thanks
Flying F