Nah, keep the 8400. The 8500 is the same chip, they basically just increased the multiplier. You can do that yourself, really, if you decided to do any overclocking.
The 4850 would do you good. The 4870 is more powerful, but the lower cost of the 4850 would allow you to get a decent after-market cooler for it so it can be overclocked easier.
Either way, go for the higher memory if at all possible. My 3850 works great, but it's shortfall of GDDR holds it back.
hey im a bit confused with directX, these new cards support directX 10.1 so shouldn't there be a directx 10.1 installation? the card came with 9.0 and i can't find 10.1 at microsoft.com
oic. no prob then..
would you (or someone) happen to know much about virtualization? what would be the better host, Windows vista ultimate 64 or Kubuntu linux 64?