hey i'm wondering is there a big differents from the 1.8 celeron to a P4 2.4 cpu. 533 FSB. have about 512 Sdram in the units. GF2 card. don't want to waste money if there is something else that would do me more good then changing the cpu's, I can't go over 400/533 FSB in these. they play tons of games. Thanks