What's up with the scrollbar?

[Frank Parish]

I just had a new hardrive installed and since I got it back online the scrollbar on anybodys webpage doesn't run smooth like it always did. It just jumps a notch or two with what looks to be a wave coming through the page in whatever direction you scroll. The mouse has a wheel but either way I try to scroll doesn't work like it should. Could it just be the mouse or something else?

[Jack Stoner]

There is a mouse setup in the Control Panel. There is an option for veritical scrolling with the wheel.