PSU for 6970 CF

[hardboy]

Will this rig run perfect on my existing Coolermaster SilentProM 850 watts PSU?

Core i7 2600k @ 1.4V OC
2x4gb RAM XMS3 OCed
3x2 TB internal WD black AND seagate xt mis plus 2x2TB extenal
wifi card
asus xonar dx
2 dvd rw
keyboards
mouse
2 other usb devices
6970 cf(currently single)
128+gb ssd
cm v6gt cooler
cm haf 932 with supplied fans

Do I need to consider a 1000 watts PSU for 2+ years of perfect usage or will this 850 do?

 

[WaTaGuMp]

Should be enough.

 

[bobwagner]

I just bought a kill-a-watt to see what my system draws. With Prime95 AND Furmark both running at full blast, I saw a peak of only 550w. My relevant specs:

2600k @ 1.2v
4x4GB RAM
120GB SSD
500GB HDD
2x 6970 CF
HX850 PSU

You have a couple more things installed than me but they draw very little power relative to the big items. The CPU overvolt won't make that big of a difference either. Given that I have 300w of headroom with my 850w, I'd say that have absolutely nothing to worry about with your current setup.

Oh, and if you're curious about normal gaming workload...DiRT 2 4800x1200 eyefinity at max settings with 4x AA only pushes system to like 350w peak.

 

[hardboy]

How does my PSU compare to the HX850 apart from the slightly lower efficiency ie, more wastage of power which raises my bill. Apart from that, how does it compare?

 

[bobwagner]

Your PSU is quite good. When I was shopping for PSUs, it was my second choice behind the HX850. I was actually gonna get the CM PSU because it was a better value but stumbled upon a nice rebate for the HX.

Technically speaking, the HX has lower ripples, higher efficiency, and has a higher measured max load (it can supply up to 1000w whereas the CM supplies up to 900w). Practically speaking, it's not gonna make a difference because you're not gonna draw anywhere near that.

And just to put things into perspective, when I was researching PSUs, the CM was better than just about every other 850w (with the exception of the HX850) in most areas so yea, you'll be fine.

How does my PSU compare to the HX850 apart from the slightly lower efficiency ie, more wastage of power which raises my bill. Apart from that, how does it compare?