Overclocking
Always nice to know that Sapphire includes an overclocked BIOS for those who want the extra speed, but the 1,050MHz and 5,000MHz frequencies are a little conservative; we know that Radeon HD 7870s typically go much further.
Sticking to stock voltage, we were easily able to bump up the card to 1,175MHz on core and an effective 5,400MHz on memory. Sapphire's using Elpida memory which doesn't appear to overclock quite as well as the Hynix modules used on previous cards, but the speed increase is healthy nonetheless.
At these frequencies, Sapphire's HD 7870 Flex GHz Edition is able to offer Radeon HD 7950-like performance.
