OCC has published a new review on the Sapphire Toxic HD4850

With a card that is overclocked well above the standard version, there is usually very little overhead to push the video card even further without voltage or BIOS mods that, of course, void your warranty. With the additional cooling capabilities of the Toxic HD4850 I was able to max out the Catalyst Control Panel clock speeds on just the first go-round. 700MHz on the core and 1200 on the memory - not too shabby! Then I started to push further. But, to do so, I needed to download and use the AMD GPU clock tool. This utility allowed me to set clock and memory speeds above those from the CCC. The highest GPU core speed that was at least 3DMark06 stable was 740/1212; unfortunately, this was stable only for just the Futuremark benchmark. So, I started backpedal.ing until I finally stopped at 731MHz on the GPU core and 1206MHz on the memory. This setup was good for all of our benchmark suite, as well as an extended COD4 session just to verify that the
settings were indeed "good". The additional cooling that is offered by the Zalman cooler kept the temperatures in check, with a maximum temperature of 64 Celsius in my 27 Celsius room.

Sapphire Toxic HD4850 Review