If you are looking for an exceptional 850 W power supply, OCZ Z Series 850 W is definitely a terrific choice, especially now that OCZ dropped its price to USD 200 (USD 170 with a mail-in rebate and free shipping at Newegg.com). It competes directly with Corsair HX850W, which costs USD 190 and has comparable performance. You see, Ecos Consulting, the company behind 80 Plus, gave HX850W their Gold certification, but Corsair decided to downgrade this unit to Silver because it couldn’t deliver 87% efficiency at full load at real-world temperatures.

Corsair HX850W has some advantages over OCZ Z Series 850 W: its efficiency was a tiny bit higher when we pulled up to 60% from its labeled load (i.e., up to 510 W; OCZ model achieved efficiency a little bit higher above that) and comes with six power connectors for video cards, supporting three-way SLI, while this model from OCZ comes with the standard four connectors. On SATA connectors both models have 12, but this OCZ model has only three peripheral power connectors, while HX850W comes with another 12.

OCZ Z Series 850 W is an excellent product and the rebate and the free shipping will probably overcome these small details. Unless you really need more cables; then you will better off with HX850W.