Its the psu not giving sufficient power to the board and other hardware such as the hard drive, so therfore when it boots ..since it isnt producing enough poer the hard drive doesnt kick in and the whole thing simply collapses.
cheap ones on ebay.
you basically need max of 12w per hardware item, so if you have a graphics card, hard drive and a dvd drive then 300 watts should be good, but i you run a powerful system like a core 2 duo or quad core system and you are a gamer or encoder loo for 700 watt psu, (look at paying about 40ÂŁ for a good one to last atx style i think)
Mathew lisett
December 2007