I think going to 2mb ram is unnecessary unless you are running Vista. I have only 1 mb ram and it runs perfectly fine at 525FSB with my E6300 P5B.
One very smart self-taught expert recently told me that 2mb or more of ram actually slows the system down, but you should have that theory corobborated before taking it as gospel.
When I sold my first set of ram (they were duds, only did 700MHz), I ran my system with a single 512mb chip for a couple of weeks (until I got my new Crucial Ballistix PC6400
) . With only 512 it was noticeably a slight bit slower when refreshing Windows screens, for instance, but you would get used to that within minutes. With most applications 512mb works fine.
More important is the quality of ram, my Ballistix run at 4-5-5-12 timings at 525 MHz...pretty good for DDR800 MHz ram! You can buy brand new (Micron D9GMH) 512mb sticks for $39 on EBay.