I ran Diablo2 and Quake3 at the same time.
I still couldn't get it to go over 384MB.
I had to have to have both D2 and Q3 going to break the 256MB mark.
You won't notice much difference from 256MB to 512MB now, but with RAM so cheap it's not going to hurt you to get the extra.
I'm sure we'll need it eventually, especially if you upgrade to Windows extra ram-pig.
<< 2000 for games only? New one on me. >>
Just curious why? Win9x wasn't designed as a gaming OS, games were designed to it, because that's what most home users currently use (and you won't see many people at work firing up a big Q3A free for all on their business network, which is primarly NT4, not many home users on NT4). WinXP and Win2k are both the NT5 core, and that will become standard for home as well. All new games will be designed for the NT5 core, and Win2k will blow 9x away. Even current games run no worse on Win2k than they do on Win9x unless you have a Radeon, and that's just becuase ATi has 3 chimpanzees and a guy with no fingers as a driver development team. Win2k is a perfectly good gaming platform, and a far more stable one to. I run Win2k only and gaming is the primary use for my computer.
Edit: oh unless you play dos games...I can't get my SBLive! to generate sound in DOS...so if I have a doom craving I either need a bootdisk or I have to play soundless.
But I've run Glide, OpenGL, DirectX and even WinG (old Win3.11 gaming API..sorta like an early DirectX, at least for video) games under Win2k. They all run great.