Medieval has a really inefficient engine, and its sys req is horrendous. I've heard that the developers over at CA on average are running the RTW themselves on Athlon 1800+ with 512 RAM and GeForce 3. Someone said that on a different board, so I can't guarantee that it's true. You should be ok with that setup, because in one of the articles on RTW the guy at CA says that they are running the game quite happily on a Pentium 3 800 Mhz laptop with 256 RAM and GeForce2Go, or something. I don't trust that, but oh well. You never know, maybe quite happily in his book is 640x480, 16-bit color and 20 frames per second. (I have a p4 1.6 Ghz with a GeForce 3, so I hope the same, for my sake).