I think you can do it with 3G of ram and the hardware you are using. if you use something like keyclone you can limit the maximum fps each uses if you are over working it. I find that the video card was a major factor, followed by ram. your video card sounds awsome but you will probably need about 512M/wow maybe 600M/wow which is somewhere between 2.5G and 3G. Vista eats up ram all by itself but eventualy it will be paged out. I say try the temp account thing and see how it goes. x64 will open up the ram over 3.2G. I use vista x64 myself and it works fine ( well, as fine as vista x32 does ). do you have two monitors? maybe the main could be on one monitor and the other 4 on the second monitor