I have A Sony Vaio laptop

Pentium 4
CPU 3.06Mhz
704mb of Ram

i use Cubase sx2

i had 512 of ram just got another 512 so i have 700+

i find that my cpu is burning up when i add plugins to my audio tracks and midi tracks.

Why should this be so if i have a decent amount of ram...

i am eventually going to upgrade to another 512 so i will have 1 gig..

But my sony vaio can only be expanded up to 1 gig so im limited...

Should i sell my laptop and go Desktop i have never been a big fan of macs

Any help would be apreciated

Jeremy