The easiest way to achieve that goal is to go overboard now. I've had my current rig for 3 years now and it's running SH4 U-Boat expansion on full graphics and doesnt flinch untill high time compression and convoys entering the area. Graphics wise the game looks fantastic and runs just as nicely.
Rig
-Vista Home Premium 64 Bit
-AMD Athalon 64 FX-55 Proc 2.61 GHz
-2 Gig Corsair DDR (Cant remember the full name but it's their gaming module)
-NVidia 8800 GTS 640MB version
-Lots (3) of SATA Hard Drives, game is installed on a 72 GB Raptor
-Creative X-fi Platinum
Rates a solid 4.3 in Vista's "Experience Index" with the lowest being the Processor followed by the RAM. I plan on overhauling this rig this summer by adding another NVidia 8800 GTS 640MB in SLI and, 4 Gig DDR2 RAM, and a new Dual or Quad Core processor (AMD of course!
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