I was wondering what would be a better upgrade to increase overall performance. Current system: Q6600, 4GB DDR2, Asus P5qSE board running on pny gtx480. Mostly running playable metro 2033 on very high but when a lot of action come there some little lag spike. Would it better to upgrade to X58 board, I7 950, 6GB DDR3(540$ upgrade) or getting SSD Drive(200$ upgrade).