Enough for crossfire?

[zMarkon]

Hey,

So i've been told before that my PSU would be enough for xfire 7950's but i've seen websites that you enter the build and it tells you the recommended wattage. Two have recommended 800W and one 550W. I'm using the Corsair GS 700W PSU. Can anyone tell me for sure if I could crossfire 7950's with it?

Full build:
i5 4670K
MSI Z87-G45
1TB HDD
128GB SSD
Corsair H100
and hopefully 2x IceQ 7950's

Thanks

 

[HecFam]

i Currently have 2 7950s & an AMD 8350 on a XFX 650W PSU. I must say i feel mine just about manages it. I've bought a power monitor just to see how much it pulls from the wall, since it has a problem booting sometimes which i think is related to not enough juice. So you should be ok, but you may not have too much headroom.

Ill see how much it draws from the wall once the thingy comes.

 

[Avenged7Fold]

i Currently have 2 7950s & an AMD 8350 on a XFX 650W PSU. I must say i feel mine just about manages it. I've bought a power monitor just to see how much it pulls from the wall, since it has a problem booting sometimes which i think is related to not enough juice. So you should be ok, but you may not have too much headroom.

Ill see how much it draws from the wall once the thingy comes.

You are probably right about the booting, it is the time where a PC has the biggest spike in power. If the PSU was not manufactured by seasonic and instead by a mediocre make, it probably wouldn't have managed it at all.


to OP:
I would say that your PSU is probably enough but that there is a risk to it that will be ongoing and with them getting worse over time, it'd be worth buying one now than later. This way, you have less risk of components and PC is more unlikely to go out of commission. I would recommend 800 Watts for a bit of clearance in case in the future, you do another upgrade which will require a bit more juice.

 

[d_brennen]

For a CF 7950 setup, you'd need ~360w @ 30A ish for the cards alone flat out, add in some wriggle room for CPU, board, drives etc. and you're looking north of 500w/45A, which your GS should cope fine with.

That's probably beyond gaming levels of power draw, something silly like FurMark or some such.

http://www.hardwaresecrets.com/article/Corsair-GS700-Bronze-Power-Supply-Review/1617/7

Please feel free to correct me anyone

 

[Confused Stu]

You'll be fine with a decent brand 700W PSU if you're not overclocking. You should even be fine if you're putting a mild overclock on CPU and/or GPUs, but you may find some issues if you try to heavily overclock.

I've got my PC plugged into one of those little meters HecFam mentioned - I got mine from a High Street catalogue shop. It shows my PC pulls about 600-650W from the wall when gaming at 5760x1080 with the CPU at 4.6GHz and the 7970's at 1050/1500. Bear in mind your CPU and GPU should pull less power than mine, and that I'm measuring from the wall and PSUs quote for power delivered into the PC (so if I'm pulling 600W at 80% efficiency, my PSU is actually delivering about 500W of it's rated 750W).

I did once see if I could run a Sleeping Dogs benchmark with both GPUs overclocked and overvolted to 1.3v. My power meter in the wall registered 933W before my computer froze and rebooted. Like I said, a decent 700W PSU should give you the headroom for a mild overclock, but don't go silly.

 

[zMarkon]

Appreciate all the replies, think i'll take the plunge and get another 7950 as i'm having no problem with temps etc and if my PSU can handle both @ stock speeds or even a mild overclock then its worth it rather than having to spend a lot more on a single GPU.