Overclocking Sapphire HD4850 but no performance

[fastrod]

I have Sapphire HD4850 and i have tried to overclocked my graphics card recently. I used Catalyst Control Center for overclocking.I have both Core Clock and Memory Clock increases with very small increments starting. Then I run Far Cry 2 benchmark.but with increased values of overclocking both are average that minimum and maximum values of the images per second is lower than on standard settings. whats wrong here ? can some one solve this problem ?

[Omari]

If the bar is higher, the chip is also warmer when the security mechanism is too warm may be the card for self problem. Time the clock rates observed under load?

[JAMES_911]

try with the Riva Tuner overclocked try to the maximum value of FPS have increased, the minimum value of 3 FPS in comparison with the values at standard clock fallen. Will Crysis equal times, because it is a benchmark tool that can help.