Iria

SLI mode on the 9800GTX+ was easy to enable and performance of two of these cards is faster than a single GeForce GTX280 card installed in some situations and nearly as fast in others. The power requirements are more but you get the performance of a faster card for a lower price. Performance of two 9800GTX+ cards in SLI in fact exceeds that of the Radeon HD 4870 X2 card from ATI meaning that two of these cards are as fast as any single card on the market today. The GeForce 9800GTX+ is a fast card, faster than the original 9800GTX. There are already 9800GTX cards that are overclocked higher than this however, and the target of this card the HD 4850 has healthy competition with this card. The wildcard is hardware acceleration for PhysX games which can make a huge difference in frame rate in supported applications.
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Source: Motherboards
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