[Moved to Hardware forum.]
You should seriously consider quadrupling that amount of RAM if you want to run Premiere Pro.
Premiere Pro from CS5 onward is 64bits... which means it needs a 64bit operating system... even 4Gig is barely enough to START the OS and PPro, but not to actually DO anything
16Gig on a modern motherboard would be my suggested minumum
Adobe's MINimums http://www.adobe.com/products/premiere/tech-specs.html
This message has a really good picture showing requirements
Click the picture to expand it to readable size
More about Requirements http://forums.adobe.com/thread/618058
With so little RAM, what are your system specs?