With a stock baseline set at 750Mhz Core and 800Mhz memory, through constant testing and benchmarking, I was able to push the core up to 820Mhz for an additional 70Mhz and the memory could be increased all the way up to 830Mhz for a 30Mhz increase. This is a 10Mhz decrease from previous HD4770 models previously reviewed and it has to be directly due to the poor memory cooling. but will it affect the overclocking over all performance? You will see in the upcoming benchmarking results.