Ravyu

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Mar 8, 2012
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Single-card? Obviously the dual-GPU GTX 690. Ever? GTX 690 in SLI (I think, or maybe HD 7970 GHz in CFX, but that might have many issues)
 

Sumukh_Bhagat

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Nov 11, 2012
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Single GPU Range
Radeon 7970 followed by GTX 680

Dual GPU Range
GTX 690 followed by Radeon 7990 (7970x2)

I am a Nvidia fan but I would still say the best is 7970, because you don't need anything more than this beast. Its best purchase for its performance and price.

 
Crossfire is for AMD cards, SLI is equivalent to Crossfire but for Nvidia cards.
Cant really answer that question, as it is very subjective to what games you play. Some games are very well set for multiple GPU's while others aren't so well optimized and suffer for it.

Also theres no point Crossfire/SLI'ing lower end cards when you can just buy a single card of equivalent strength and price. Only worth doing Crossfire/SLI when your talking higher end cards or if you already own a card.

Also we need more info. If your after advice on which card to get, we need to know your budget and usage.
 

Ravyu

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Mar 8, 2012
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Thats pure BS, a single GTX 690 does not beat a 7970 CF