Scanner Problem, HP

Replaced an HP Deskjet 4280 with a HP Deskjet 2480 as the scanner sensor died. 4280 was excellent, scanning with the HP software was fine. The 2480 scan with the HP software is strange, runs a preview scan fairly normally but when scanning to the computer takes an extremely long time and produces an odd scan, losing definition when zoomed out.
Switched to WIA scan and sscn is quick with normal output.

All latest HP drivers. Have now uninstalled HP software except basic drivers.

OS Name Microsoft Windows XP Home Edition
Version 5.1.2600 Service Pack 3 Build 2600
OS Manufacturer Microsoft Corporation
System Name CUBE
System Manufacturer ASUSTek Computer INC.
System Model P5L-MX
System Type X86-based PC
Processor x86 Family 6 Model 15 Stepping 2 GenuineIntel ~1599 Mhz
BIOS Version/Date American Megatrends Inc. 0901, 13/04/2007
SMBIOS Version 2.4
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume2
Locale United Kingdom
Hardware Abstraction Layer Version = "5.1.2600.5512 (xpsp.080413-2111) "
Time Zone GMT Daylight Time
Total Physical Memory 3,072.00 MB
Available Physical Memory 2.18 GB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 4.34 GB
Page File C:\pagefile.sys

I assume a conflict somewhere, vague memory from many years ago with a scanner on Win 95, changing one setting on the PC improved matters dramatically but can't remember where!