Bitcoin Forum

Bitcoin => Mining => Topic started by: hashking on February 28, 2012, 01:59:28 PM



Title: Radeon 7970
Post by: hashking on February 28, 2012, 01:59:28 PM
I was going to try and get four 7970 into one rig. Are they worth the money and would an 850 power supply work.  I currently run 2 5870', 2 5850's on one of these power supplies.  If not any suggestion on power supply. 


Title: Re: Radeon 7970
Post by: matthewh3 on February 28, 2012, 02:16:21 PM
I was going to try and get four 7970 into one rig. Are they worth the money and would an 850 power supply work.  I currently run 2 5870', 2 5850's on one of these power supplies.  If not any suggestion on power supply. 

Each Radeon HD 7970 uses 250W under load so do the maths.  I think you would need at least a 1400W PSU if you were to run 24/7 and you wanted the PSU to last over twelve months.


Title: Re: Radeon 7970
Post by: DeathAndTaxes on February 28, 2012, 03:06:02 PM
1200 or 1250W PSU should be fine if:
a) good brand
b) high efficiency (80-Plus Gold or better).

850W is a good way to kill a PSU or the hardware or you (when your significant other kills your for burning down the house).


Title: Re: Radeon 7970
Post by: S. Omega on February 28, 2012, 03:36:10 PM
Not saying you shouldn't have some breathing room; but for you consideration:
I ran 2x Radeon HD6990's (combined with: i5 2500K, 8Gb RAM, 1 SSD, 1 HDD, 5 Fans) 24/7 for a couple of months on a Seasonic PSU rated for 850W, before repurposing the system for everyday use. Works fine, still.

Granted, I did undervolt the GPU's; but they still pumped out 1520 Mh/s.


Title: Re: Radeon 7970
Post by: slider1978 on February 28, 2012, 04:37:22 PM
I was going to try and get four 7970 into one rig. Are they worth the money and would an 850 power supply work.  I currently run 2 5870', 2 5850's on one of these power supplies.  If not any suggestion on power supply. 

7970 require 8 pin and 6 pin connectors, two connectors per card.  Probably 150-200W on the 8 pin cable, another 50-100 on the 6 pin cable.

Now, you figure out the right PSU for your 4 card setup.

or PSU'S

As for them being worth the money, I'm running a single right now and am happy with the output. I plan on adding 3 more in the next month or so, unless the 7990's come out.


Title: Re: Radeon 7970
Post by: JWU42 on February 29, 2012, 03:25:06 AM
Speaking as someone with 2 4x7970 rigs  :P

Running Seasonic 1250 gold psu...

1050/900 :: 225-230 per card (1060-1080 for the rig).

1150/1000 :: 245-255 per card (1130-1150 for the rig).

Each rig has 2 x 120x35mm Delta fans that eat ~10W per - so you could drop these numbers by 20W, accordingly.