Have you tried readyboost? It is a way of wpeeding up RAM cache by writing to a USB device rather than a disk drive. The premise behind this being that reads and writes are faster than writing to a spinning disk.
In terms of performance, its good especially moving in between applications and loading programs. I always recomend this for people running 32 bit 7 on older computers.
check out this blog post
http://www.groovypost.com/howto/microsoft/vista/increase-windows-vista-performance-using-readyboost/
