Computer Lag

I'm running an MSI RX480 Motherboard with a AMD athlon 64 3800+
planning to upgrade to a AMD 64 FX55 or a duel Core AMD later on down
the line. But my Question is tha When I try to restart is seems to lag
so much that you half to restart is by hand. What can this be . I'm
running a 450 watt power unit but next month I'm putting in a 600 watt
Ultra X2 power supply which may fix one of my problems. but what woud
be a good type of ram. I'm running a Gig of Micron DDR PC3200 with
heatsinks. Please help me of what I may be doing wrong or pass any info
you may know my way please.Thanks!!!!