EVGA has now released the EPower Board, a VRM board which can be hooked up to a motherboard and/or graphics card (some soldering required) and provide more watts required for uber-overclocking.
This warranty-voiding device features a 10-phase main output, a 3-phase secondary output, digital PWM (for the main output), three 6-pin PCIe power connectors, plus EVBot and fan support. The EPower Board costs $99.99 and is "intended only for advanced users with electronics experience."
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