Wow, you are talking about a good old fashioned RAMDRIVE. That is one I have not tinkered with for a long, long time (since Win98). Talk about a Blast from the past.... Deja Vu all over again.
..but the others are correct, The ram drive would work for CPU intensive games, but for the newer GPU games you would need graphics help..and a RAMDRIVE would not do much there.
Lots of info out there: http://www.google.com/search?source=...10&oq=ramdrive
Good Luck, let us know how it works for you