It’s very early days for nVidia’s flagship GTX 590 but it has already had a serious fault with the over-current protection (OCP) built into the card, which controls how much current is allowed through the circuitry, important when overclocking or under heavy GPU loads.
nVidia recommend anyone using the GTX 590 with a reference cooler to stick to the default voltage when overclocking, and avoid working around overcurrent protection mechanisms for stress applications. They say this will help maintain the GTX 590's great combination of acoustics, performance, and reliability.
nVidia have worked with several watercooling companies to develop waterblocks for the GTX 590, and these will help provide additional margin for overclocking, but even with watercooling they recommend users stay within 12.5-25mV of the default voltage in order to minimize risk.
The current drivers can be found here: 64 bit and 32 bit.
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