PSU for 7970 crossfire.....
- Thread starter Briggsy
- Start date
Excalabur50
Well-known member
Go to this site put in your specs and see if you have enough http://extreme.outervision.com/psucalculatorlite.jsp
Briggsy
New member
Well the quoted website recommends 877W as standard for an overclocked gaming rig in crossfire, I will be adding a water cooling loop in soon so I guess I should upgrade to a 1000/1200w....
Any recommendations?
Thanks
Excalabur50
Well-known member
Yes mate the AX1200 from Corsair will fullfill your needs nicely!
ruthless_villain
New member
1000W
http://www.scan.co.u...ire-eps-12v-qui
1200W
http://www.scan.co.uk/products/1200...80-plus-gold-sli-crossfire-eps-12v-quiet-fan-
really good value for money, quiet, have nearly all of the corsair features... look pretty good as well
http://www.scan.co.u...ire-eps-12v-qui
1200W
http://www.scan.co.uk/products/1200...80-plus-gold-sli-crossfire-eps-12v-quiet-fan-
really good value for money, quiet, have nearly all of the corsair features... look pretty good as well
KING_OF_SAND
New member
AX850 would be more than enough.
Rastalovich
New member
I was gonna say, a quality 850+ watt.
750w I just wouldn't be happy for 24/7 use and overclocking. Testing - I'd probably give it a go if it was a good one.
750w I just wouldn't be happy for 24/7 use and overclocking. Testing - I'd probably give it a go if it was a good one.
SmoulderingCircuits
New member
Cougar 1050w
KING_OF_SAND
New member
You would be just as good with a nice 750w.
Master&Puppet
New member
Based on maximum power draw with some rounding up:
Your cpu is probably drawing ~200W
2x 7970s at stock ~550W
plus ~100W for OverClocking power draw, hdds, ssds, fans, leds and all the other parapehenalia you might have.
= 850W
If you are often running the system hard then I'd go for an 850W. But it's unlikely you'd keep the system running at maximum like that so your 750 will probably be fine. The PSU can actually supply more than 750W in short periods if it needs to - it's power rating is based upon a maximum sustainable figure.
It's quite easy to measure you own system's power draw if you have a energy consumption monitoring plug. In your case you just need to find out:
1. How much your current system is drawing (stress test both the cpu and gpu at the same time).
2. How much of that is consumed by the GPU (run the system without the gpu and stress test the cpu).
Then you can add the figure in point 2 to the one in point 1 and you have your xf consumption.
Bear in mind that the efficiency of your PSU comes into play because the system will actually be drawing xx% of the wall plug's figure. I.e:
if your wall plug is measureing 500W and your psu is rated at 80% then the system is drawing 400W (500*80%) because 100W is being lost in heat.
Conversely a 500w PSU with an 80% energy rating can actually draw 625W (or even slighly more in bursts) from the wall but will only supply 500W to the system.
Your cpu is probably drawing ~200W
2x 7970s at stock ~550W
plus ~100W for OverClocking power draw, hdds, ssds, fans, leds and all the other parapehenalia you might have.
= 850W
If you are often running the system hard then I'd go for an 850W. But it's unlikely you'd keep the system running at maximum like that so your 750 will probably be fine. The PSU can actually supply more than 750W in short periods if it needs to - it's power rating is based upon a maximum sustainable figure.
It's quite easy to measure you own system's power draw if you have a energy consumption monitoring plug. In your case you just need to find out:
1. How much your current system is drawing (stress test both the cpu and gpu at the same time).
2. How much of that is consumed by the GPU (run the system without the gpu and stress test the cpu).
Then you can add the figure in point 2 to the one in point 1 and you have your xf consumption.
Bear in mind that the efficiency of your PSU comes into play because the system will actually be drawing xx% of the wall plug's figure. I.e:
if your wall plug is measureing 500W and your psu is rated at 80% then the system is drawing 400W (500*80%) because 100W is being lost in heat.
Conversely a 500w PSU with an 80% energy rating can actually draw 625W (or even slighly more in bursts) from the wall but will only supply 500W to the system.
Briggsy
New member
I have an AX750 already......but I might go for a AX1200 to be on the safe side.
Calibretto
New member
AX850 end of...
Quieter, smaller and the hell of a nice PSU to have to deal with.
My only other suggestion would be the 860 watt Seasonic Platinum
Quieter, smaller and the hell of a nice PSU to have to deal with.
My only other suggestion would be the 860 watt Seasonic Platinum
Calibretto
New member
I think so
KING_OF_SAND
New member
Absolutely. I think the reason you are so concerned with getting a 1000w+ PSU is because you are thinking you may get to close to the 850w mark. Being concerned about this is good, MOST cheap PSU's when they say 850w they actually mean 700w. Because the Corsair 850 is so good you can actually hit the 850w mark and still be fine. In fact most high end PSUs such as the AX series can handle a little more than speced. 850w is just what they are tested at.
