No fps increase playing rift or mafia 2 after overclocking gt 220

[pieboy12321]

I overclocked my gt 220 from 625 core clock 1360 shader clock and 490 memory clock to 800 core 1740 shader and 640 memory clock. I have seen no fps increase and if anything have seen about a 5-8 fps decrease. When I change back to original settings the fps remains the same. Have i screwed my card or something, because now I get less fps in default settings also. Anyone know why this is? Thanks. (I also benchmarked Mafia 2 after reverting to original settings and I get less fps than i used to, overclocked theres no difference in that game either.

System specs:
AMD Athlon II X2 250 3.0Ghz
Nvidia geforece gt 220
4gb ram

 

[Spesh]

Sounds like you probably haven't given them a sufficient voltage increase. If the card can't get the power that it needs, it will result in an unstable overclock which quite often also results in lower performance despite the higher clock speeds.

What program are you using to overclock the card?