BFGTech’s GeForce 8600GTS OC2 increases the default speeds 720MHz GPU and 1110MHz RAM, which does give you a good jump over a non-overclocked 8600GTS.  The problem is that a 320MB 8800GTS can be had for almost the same money, and Boot Daily’s benchmarks show it takes two to compete with the faster card.
“Always the innovator, BFG Technologies has released an updated version of its 8600GTS dubbed the OC2 and incorporates the company’s latest thermal technology which it calls ThermoIntelligence.”

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