Slow Slow XP Install and run

I have just assembled a new PC: as follows:
ASUS A8N SLI SE
Athlon 64 3200+
200GB Barracuda S150 SATA
1GB Kingston KVR400X64C3A/1G RAM
HP DVD L/Scribe
Gainward GF 6500 256MB PCIE graphics card.
New OEM version of XP Pro.

XP Pro installation took over 10 hours - disk formatting 1 partition was
fairly quick and all the Windows directories were created quickly, then the
filecopying bit fron the CD took about 5 hours and the actual installation
took another 5 hours.
When copying, the DVD drive light would flash as it read some data, then it
would sit there for minutes before there was any HD light activity.

When XP was eventually running it is very slow - it takes many minutes to
start up then everything takes an age to happen, i.e click on a button - no
initial response, then 10-20 secs later something happens.

Any clues anyone?