The 5450 is not a gaming card, so overclocking won't solve your issues. The biggest improvement you could get is to reduce the resolution you game at, to as low as you can stand it. If you're over 1280x1024 or 720p, it's already too high. If you could drop down to 1024x768 or lower that would be best. I know, because I used a card like this to play TF2 and CS.