My client's laptop is going really really slowly.
I've done:

AVG - clean
spyware - clean
malware - clean
hijack this - clean
CCleaner and Defrag done

I did a Memtest - nothing wrong there.
I performed storage tests with TuffTest - interestly, the Internal Controller Diagnostic Test failed, but the Seek Test and the Surface Analysis passed!!

I downloaded the manufacturer's disk test, and that passed. Then I ran SMART with the Stellar Smart Early Disk Warning System - the Fitness level on every test was 100%, except that the Seek Error rate is 32% and the Write Error Count is 22%! These don't look right.

All the processes, memory and CPU usage look fine,

51C - CPU Temp, 38C - HDD

Nothing out of the ordinary in the Event Log either.
BIOS is latest BIOS

Systems specs:

Fujitsu Siemens Amilo Pro V7010
Fujitsu PL501 motherboard
BIOS: Fujitsu Siemens / Phoenix 1.10 28/12/04

This is strange:

BelArc reports it has got 1024MB memory in slot 1, and then directly under Installed Memory, it says there's only 480MB!

FUJITSU MHT2040AT 40GB HDD
Windows XP SP3

My mate tested the disk on a Linux system and he said it was fine.

Whats happening?!