I think it's ridiculous how fast things are progressing. Just like the hp wars in the auto world, the pc world is undergoing a memory/cpu race. I think it's reasonable to just upgrade to a new system every four years. My current system's a bit old: 2Gig Ram, 2.8GHz single core, 6800GT. Yeah, it's really old.
E92 335i: Space Grey|Coral Red|Aluminum Trim
Hold out for the BRZ STI or... Rocket Bunny FRS.