Overclocking

Sapphire's Atomic Edition HD 3870 comes pre-overclocked out of the box with clocks of 825 MHz and 1200 MHz. We used ATITool and AMD overclocking software to adjust the clocks in order to detect the maximum stable clock frequency.



The final overclocks of our card are 864 MHz Core (5 % overclock) and 1251 MHz Memory (4 % overclock). While both overclocks may seem slim, you also have to put them in contrast to the reference design clocks of 777 MHz / 1126 MHz. Then the overclocks are 11% for both memory and core. This is quite nice for a single slot card I must say.


While the idle temperature seems to be fine, the load temperatures are quite high. For a single slot cooler the results are fine, but I had expected a bit more from the Vapor-X cooling technology. The reference design HD 3870 with a dual-slot cooler reaches about 90°C too during load.