Old Scanner runs very slow on Win Xp PC

I just bought a new HP 522a PC which runs Windows XP Home Ed. I have a 600 III + paraellel scanner. It ran fine on my old slow Win 98 PC but now it scans so slowly its terrible. I installed both XP, Win 2000 and other drivers but none fixed it. I also ran the suggested patches from the scanner suppliers Mustek.

Can anyone suggest a fix?

Thanks Bruce