sonyvegas editing

I have a fairly aged Acer Laptop that I started using for editing in sony vegas. It's got an Intel Pentium 2.20 GHz processor and 4GB of installed ram. The laptop runs smooth and doesn't give me any problems but it's not the best for prerendering during editing and render time is not the fastest. For example, if I want to prerender and see progress mid edit, it won't render most of the selected clip(s) as well as the best quality, I have to resort to dropping the view on the right corner to maybe draft (half) quality. I was wondering if I could upgrade the ram and if that would help with my rendering.