I had the misfortune recently of installing XP SP2 onto a good friend's Dell Inspiron 1150. I call it mistfortunate because immediately after having done this and rebooting, the whole thing ended up being incredibly slow, taking about 5 times longer to do anything than would be normally expected.
In the end, and thanks to Google search, I discovered that the solution was to rollback the driver for the processor. Windows complained about the earlier version not being signed but, after doing so anyway and rebooting, everything was back to its speedy self. It's not clear what the conflict is between SP2's newer version of the Celeron driver and the Dell Inspiron, but there's definitely something that's not right.
XP SP2 on Dell Inspiron makes it extremely slow.
Moderator: jasonb