OCC has published a new review of the Sapphire HD 3870

The most that I could get out of this card was the core clock at 850MHz from the stock 777MHz and the memory at almost 1300 from the stock 1126. I re-ran all of the benchmarks with the overclocked settings. The
overclocking took place with the newest drivers installed. The overclocked results are denoted by "Overclocked" in the graphs.

Sapphire HD 3870 Review Overclocked