Few years ago I purchased an Antec TruePower Quattro 850 watts PSU. That time I made my PSU purchased, a 1,000 watts or higher rated PSU seems over the top (an 850 watts PSU seems to be a logical choice). As time goes by, a much higher wattage PSU hence become common. I'm now using (2) dual GPU Radeon HD 4870X2 video cards or quad CrossfireX set up. A single video card is rated at minimum of 650 watts & if using (2), 1,000 watts or higher PSU is the recommended. I still manage to use my video cards using an 850 watts PSU without any problems. Do I need to upgrade my PSU to much higher wattage if I'm going to overclock my rig? Upgrading my PSU also means upgrading my UPS to a much higher wattage which seems to be costly. I'm also planning to buy some stuff for my next PC upgrade using the new Sandy Bridge core processor. Below is my current pc set up (most components I already owned & used for my current PC):
PC Case - Zalman FC- ZE1 Fatal1ty Champion Series (own)
Motherboard - Gigabyte GA-P67A-UD7 (plan to buy)
CPU - I7 2600K 3.4 GHz Quad Core CPU (plan to buy)
CPU Cooler - CoolIt Vantage A.L.C. CPU water cooler (own)
RAM - Corsair Dual Channel DDR3 2000 MHz memory ( plan to buy)
Blu-ray Writer - Liteon IHBS212 internal 12X BD writer with 3D Playback (own)
Blu-ray ROM - Liteon iHOS104 internal SATA BD ROM (own)
Video Card - Sapphire Radeon HD 4870X2 (2) on Quad CrossfireX (own)
PSU - Antec Quatrro 850 watts Continues PSU (own)
UPS - APC Back Up UPS XS 1500 865 watts UPS (own)
Monitor - Viewsonic FuHzion VX2265wm 120 Hz 3D gaming monitor 22 inch (own)
Soundcard - Creative Sound Blaster X-Fi Titanium Fatal1ty Pro Series (own)
Speakers - Dell 5650 5.1 channel Multimedia Home Theater Speakers Sys (own)
TV Tuner - Asus My Cinema-EHD3-100 TV Tuner card (own)
Initial info I gathered from the internet is that this new Sandy Bridge core processor can be overclocked at 5.0 GHz air cooled. I'm looking into that 5.0 GHz range but I'm not going to use an air cooled system. It's gonna be liquid cooled (CPU & GPU).
Another gamer I know on some game website made a bet that if I can bet his Benchmarck score on my next PC upgrade he's going to shut up & delete his account. He's using an overclock-friendly motherboard (EVGA 3760 A1 Classified X58) & will also be upgrading his video cards from GTX 470 to GTX 580 on SLI.
I think I can bet his score by extreme overclocking & using a liquid cooled system as will as hybrid SSD on RAID 10. It's a lot of work but hence I've already accepted his challege then the challenge is on.
A pair of 4870X2's needs "only" about 550 watts. So your PSU is adequate for your needs. But I don't think you have a whole lot of power in reserve.
No, the video card's specs say 650 watts or greater PSU is recommended. Using 2 on quad CrossfireX set up a 1,000 watts PSU is recommended. I been using 2 of this video cards for almost 2 years now using an 850 watts PSU without any wattage problem. What I'm worried about is during an extreme overclocking. I'm not sure if I have enough power to overclock.