The 600-700W range is very popular with enthusiasts who either have a pair of fairly powerful GPUs or a single top of the line GPU, as they don't quite need a kilowatt class PSU.  X-bit Labs put together a roundup which features 9 PSUs from Corsair, Chieftek, Cooler Master and Zalman some modular and some with permanently connected wiring.  It was the Corsair TX650 which received the Recommended Buy award though Cooler Master came close to winning as well.  Some of the other models fared poorly thanks to the lack of proper voltage regulation or in one case fan regulation.  Check out the full review here.

"We would like to talk about nine power supply units from the most popular 600-700 W wattage range, which represent six different series of devices from four manufacturers: Chieftec, Cooler Master, Corsair and Zalman."

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CASES & COOLING