Helping a friend with a few upgrades on a Compaq Presario S2040WM. It came with one 40g 5400rpm drive, and (only!) 128 Ram. I'd like to add a 7200 rpm West Digital drive of around 80g, one 512 stick of RAM and a 92mm Antec Smart case fan (the only fan it currently has is for the 2g AMD cpu). They only have one small PCI fax modem dialup card. It's got a 250 watt power supply - will that be enough? (I didn't see ANY graphics card in it) Thanks!