AMD Radeon HD 7990 : Powerful but Expensive Graphics Card

The 7990 follows in this line – essentially bolting two 7970 Tahiti chips onto the one card – it's perhaps surprising that we haven't seen this launch long before now.

  
The AMD Radeon HD 7990 comes with a boost clock, so it can push the total speed up to 1GHz. The memory clock of 1500MHz (6GHz DDR effective) is substantially faster than the 1375MHz (5.5GHz DDR) of the 7970.

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