Well XP shouldnt be your Os of choice even if your using only 2 cards much less 3, 4 and above. What I meant was your OS can support 1000 gpu's but if the drivers dont support it... whats the point. And I was additionally replying to the "hacked drivers" statement: because even if you change some parameter in the driver to allow 5 cards, you probably wouldnt see any scaling from the 5th card, since the rest of the driver code isnt optimized to use it.
Anyways back on topic I updated my vantage score a bit:
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