New elitegroup 915p-a motherboard, intel P4 3.0 chip, 1 gig of kingston ram ddr2, and a ATI, HISX1600xt ice Q video card. Also a new 500 watt power suppy. 2 DVD burns, zip drive, 3 1/2 floppy. in a desktop case. 16yr. old son says his games lag and computer runs slow. he is playing half life 2, and counter strike. Asking for advice on how to config for better performance