Sapphire launched new Sapphire Toxic HD 4890 in there 4800 series...

Vapor-X Cooling
Vapor Chamber Technology is based on the same principles as heatpipe technology. A liquid coolant is vaporised at a hot surface, the resulting vapor is condensed at a cold surface then the liquid is returned to the hot surface. The recirculation process is controlled by a patented wick system. SAPPHIRE Vapor-X flattens the whole system into a slim chamber - which in the graphics application is mounted in contact with the surface of the graphics chip.
Differnce b/w HD4890 and Toxic HD4890
Sapphire HD4890
Core Clock: 850MHz
Memory Clock: 975MHz,3.6gps
Sapphire Toxic HD4890
Core Clock: 960MHz
Memory Clock: 1050MHz,4.2gps
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