Radeon HD 6750 running at 120 Mhash/s table shows 167Mhash/s I'm using guiminer with flags -v -f30 -w128 under windows 7 but all i get is 120Mhash/s thats like 75% of what the table shows. Any idea why is that?
If you are using ATI Drivers 11.12 or 12.0 or above you need to set the worksize to 64.

Also the new drivers are a bit slower then pre 11.12 drivers.