It highly depends on your notebook, but most likely there is nothing you can do.. Normally notebooks aren't upgradeable to any large extent. Most of the time the best you can do is memory and maybe hard drive.
It would, however, help to know exactly what notebook you have (Make and Model).
Thermaltake Xaser II A5000C (w/ 5 case fans)
AMD 2500+ (OCed to 3200+)
Asus A7N8X Deluxe
1 Gig Corsair XMS low latency pc3200
2x 80g Maxtor SATA (w/ Raid 0)
128Mb Nvidia GeForce FX 5700 Ultra
480w Thermaltake PSU
Video Capture Card (titantv.com ROCKS!)
16 Sony DVD Rom
52x/32x/52x Optorite CDRW