ATI 4850 Overclocking Help on iMac Late 2009

[MayB]

So, I got a Battlefield 3 recently, and my iMac wasn't doing good. I had to set on medium for decent FPS (30~40), and all low to play good on multiplayer.

Then I read about overclocking ATI 4850 to desktop clock will increase the performance. So I tried to overclock using MSI Afterburner. I enabled unofficial overclocking, then I set the clocks on 625/990.

The thing is, GPU-Z and CCC recognizes the clock as 625/990, but MSI Afterburner's graph is still on default, 500/880.

So I ran the Furmark test, and the FPS and the score had no difference between defalut and overclock setting I tried. That means it actually did not applied to the graphic card.

I need help on this. Is there something I'm missing? If you can, can you give me proper steps to overclock iMac?

 

[Rodus]

I've overclocked the exact same machine using MSI afterburner so it should work. One think I did was save the profile to profile 1 and apply at startup, then locked the padlock.

 

[MatthewAMEL]

Someone beat me to it... /

 

[MombiusHibachi]

Erm...Im not exactly sure where Im going wrong with it :S I've edited the config file to Unofficialoverclockingmode = 1 yet when I try and change the values in Afterburner they flash after they have been entered then reset to the default values? Im using Catalyst 11.10 drivers downloaded from the ATI site, is the catalyst control centre causing the problem? If so.... do i delete the control centre/sticking to the drivers alone? Oh...and once overclocked...what settings are you guys running bf3 on for multiplayer?

 

[MombiusHibachi]

anyone? :/