Win Xp - Sound Card Issue

The original drivers that came wth my sound card are incompatible on WinXp.
Searched the net, found some that a lot of people said worked fine with Xp.

They installed just fine...with the exception that I cannot use the Loud and Surround functions anymore..oh well.

Now, they play just fine to, sounds good, just one exception.
If the comp is busy thinking, the sound gets super messed up.

How to put this....Uh, the sound clips with the lag of the computer. Like the sound card has been tied in with the processor so they are taking turns processing thus causing the sound to be terrible if the CPU is in use.

Where should I start to fix this???