Computer running very slow!

I dont know why my new computer is running so slow. I just go a new HP
Pavilion dv 8000 laptop. Ive dl'd a few anti spy ware programs and i have
nortan on my comp. It says i dont have a virus. Ive defraged. I have
windows XP with a turion 64 prosessior. 1gb ram. so i mean it should be
fast. im just kind of stuck, and i dont know what to try next besides
reformat. But ive already done that once and i want to figure out the
problem is. Any sugestion will help!