mouse pauses every 5 seconds?

I have a few Sun Java Desktop Systems (w2100z) with the dual AMD Opteron 250 processors and the Nvidia FX 3000 DH video card. I have the 7667 driver loaded. It's running SuSE 9.3 pro. I've noticed that there is a slight pause in mouse and monitor movement every 5 seconds or so then it jumps to catch up to where it should be. Does anyone have an idea what maybe causing this? TIA