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Bitcoin => Mining support => Topic started by: fabrizziop on July 23, 2012, 02:43:23 AM



Title: Is there anything I need to know before getting dual GPU cards?
Post by: fabrizziop on July 23, 2012, 02:43:23 AM
Hi. I'm planning to get either one 5970 or one 6990, and place it on my main rig, that currently has a 5850 and a 5830. I'll move the 5850 to the 4x PCI-E slot and leave the dual-GPU card on my 2.0 16x slot. I just want to know if I need to consider anything else before getting that card?. My PSU is an Antec Earthwatts 650W green, 80 PLUS bronze, it can give about 620W on 12V rails. Will my PSU hold up?.

Anyways, I don't think that will be too much of an issue, as I could swap my 5850 with a 5830 from another rig to lower my PSU load, but my main question is in drivers. Is there any kind of problem by mixing a 5830/5850 with a 6990 or 5970?. I'm currently using 12.1 with SDK 2.1, so I don't know if there's any common denominator for the recommended drivers of those cards.

Thanks in advance to all of you.


Title: Re: Is there anything I need to know before getting dual GPU cards?
Post by: ssateneth on July 23, 2012, 04:38:01 AM
Should work fine. I think the earthwatts are multirail though, so be careful. You might have power locked to rails that won't be available for your vid cards.

Got 2 5970, 2 5870, and 1 5850 (all reference) on a PSU with a single 860 watt 12v rail. Draws about 900 watts at the wall. It's only 83% efficient though, so probably still has some wiggle room.


Title: Re: Is there anything I need to know before getting dual GPU cards?
Post by: 420 on August 02, 2012, 07:49:46 AM
Should work fine. I think the earthwatts are multirail though, so be careful. You might have power locked to rails that won't be available for your vid cards.

Got 2 5970, 2 5870, and 1 5850 (all reference) on a PSU with a single 860 watt 12v rail. Draws about 900 watts at the wall. It's only 83% efficient though, so probably still has some wiggle room.

How much mhash are you getting out of a 5970 and at what clock rate with what miner?


Title: Re: Is there anything I need to know before getting dual GPU cards?
Post by: QiVX on August 02, 2012, 09:48:12 PM
Should work fine. I think the earthwatts are multirail though, so be careful. You might have power locked to rails that won't be available for your vid cards.

Got 2 5970, 2 5870, and 1 5850 (all reference) on a PSU with a single 860 watt 12v rail. Draws about 900 watts at the wall. It's only 83% efficient though, so probably still has some wiggle room.

How much mhash are you getting out of a 5970 and at what clock rate with what miner?

I've got 3 5970s and 1 5870 on a 1.2kW Seasonic PSU.
My 3 cards are clocked differently.
@ 850 engine I get 400 mhash a core (GPU 1)
@ 900 I get around 420 mhash a core (GPU 2)
@1000 I get 470 mhash a core

I've pushed one of my 5970s to 500 mhash a core but VRMs were in the high 90s and low 100s.