SB Audigy2 zs and gaming lag

hello all i was wondering if i can get an answer to my question

ok heres the deal....i play online games and have a geforece4 fx5200 video card and a sound blaster audigy2 zs sound card...well seems as though my sound card is causing my computer to lag while im in game i know its my sound card because i removed it and played and it ran great no lag at all..
if any one knows a setting or something to help me out that would be great. specs to follow

AMD xp 2100+
WD 60gig 7200rpm
SB audigy2 zs
GF4 FX5200 (256megs ram)
soyodragon lite kt333 mobo
640 megs ddr pc2100 ram
win98se

thanks in advance