The 6670 is OK, but the 7750 will be lots better if . Besides, whats your budget? On Newegg, you can get the 460 for $110 which is 5x better than the 6670/7750. The 460 will require a PSU upgrade, since it needs 2 PCIE connectors, but the 7750/6670 don't. But, you'll have to upgrade the PSU. Get a 500W one.