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Other => CPU/GPU Bitcoin mining hardware => Topic started by: OggerMC on May 04, 2012, 11:58:05 AM



Title: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: OggerMC on May 04, 2012, 11:58:05 AM
Hello, im just wondering if this would work.

the mainboard
http://www.sapphiretech.com/presentation/product/?cid=2&gid=1089&sgid=1099&pid=1128&psn=&lid=1&leg=0

the gpu's would be referenz 7970's + waterblock

and i was wondering if there is an PSU out there strong enough for it?

the most capable i found was this one

http://www.newegg.com/Product/Product.aspx?Item=N82E16817494006


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: oldDirty on May 04, 2012, 01:21:55 PM
10x 6+2 PCIe, you need twelve, each card need around 250W on stock clocks.
So you need to downclock the Vram and reduce the Vcore of GPU ore you plugin a second psu.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: kliffen on May 04, 2012, 01:42:57 PM
For this setup i think it would be easier to get 2 PSUs


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: Chefnet on May 04, 2012, 01:53:11 PM
yes just use 2 1000W psu's and be happy.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: DeathAndTaxes on May 04, 2012, 02:07:44 PM
One thing in your favor is waterblocks.  I think someone indicated they were getting ~30W less from the wall per card when watercooling the 7970.  Part of that is the fan but part of it is the fact that as a 28nm chip the 7970 has a lot of leakage (non switching load) and bringing the temp down helps improve that.

It would probably be easier to use 2 PSU but 1600W might work however you are going to need some kind of adapter to power the 6th card.

Might make more sense to go with 5x 7970s per rig.  Then power & connectors become a non-issue.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: OggerMC on May 04, 2012, 05:13:08 PM
yeah, but i cant fit 2 psu's into an "normal" case, i plan to run this in an case and outside 1 or 2 MO-RA's for the cooling.

Im not sure, how much space there is betwean the cards, you think i can make the water go  3 cards > rad - 3 cards > rad ?


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: DeathAndTaxes on May 04, 2012, 06:01:15 PM
No need.

You can just go 6 GPU -> t-branch-> (RAD 1 & RAD 2) ->t-branch -> back to GPUs and pump.

2x radiators in parallel will dissipate 2x the heat of 1 radiator.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: OggerMC on May 04, 2012, 06:39:10 PM
http://img7.imagebanana.com/img/87u4lmlt/76e55513_WaterCoolingOverviewsecondd.jpg

you mean instead of 1 and 2 i would put the t-benches? but how would that fit in size? i thought they would be directly next to it.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: AzN1337c0d3r on May 05, 2012, 06:57:17 PM
you mean instead of 1 and 2 i would put the t-benches? but how would that fit in size? i thought they would be directly next to it.

No I think he means get another identical radiator and then split the flow right before the radiators and merge the flows right after.  Anyways I'm not convinced of parallel loops. They require twice the component counts (two SLI links in your case) as well as a splitter for what appears to be minimal gains. See Martin (from martinsliquidlab.org) post (http://www.overclock.net/t/519131/series-versus-parallel-liquid-cooling-loops#post_6400096) on this subject.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: OggerMC on May 06, 2012, 12:12:34 AM
okay, but wont the first card be cooled the most and the last card would get only hot water?


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: twoBitBasher on May 06, 2012, 12:04:57 PM
I'd advice to always connect gpus in parallel! In series the last cards doesn't get enough cooling and the restriction of the loop is huge! Just make sure your blocks are the same make. i.e. mixing 5870s with 5970s in parallel(if you could do it) would be really bad for the ones with more restriction.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: jjiimm_64 on May 08, 2012, 01:30:10 AM

has anyone actually seen or heard of 6 79xx cards in windows?  i have 3 rigs with 5 each.  i tried to put a 6th card in but could not get windows enable the 6th card.  it sees the card but will not enable it.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: AzN1337c0d3r on May 08, 2012, 05:36:32 AM
okay, but wont the first card be cooled the most and the last card would get only hot water?

The DeltaT is negligible whether you connect series or parallel. I have my 3x 7970s in series and they have less than 2 degrees difference between them.

Parallel only makes sense when you have super-high-restriction... if you're running a CPU block, that will completely dominate the restriction so 2 GPUs in parallel or series wont change much (except the parallel loop has much higher chance of leak).

Here are my 7970s running full-tilt.

http://img232.imageshack.us/img232/8946/7970gpuloopseries.png


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: joshv06 on May 23, 2012, 11:52:46 PM
Does anyone know if it is possible to put 2 watercooled video cards right next to each other with no slot spacing? I have never seen it done, I have only seen [Video Card - Open Slot - Video Card], never [Video Card - Video Card - Video Card]. If anyone finds a pic of it done, please show me. This is all in consideration of a card like a 7970 that is capable of having a one slot bracket.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: BR0KK on May 24, 2012, 12:36:09 AM
Could propably be done with water coolers that have their inlets on the top (not like ek on the side)
There are some systems for sli or cf that feature an interconect for 3 or 4 gpus, but as i know these systems are not made for this. They are double wide, leaving a pcie slot free.

I look for a pic

And ek waterblocks are to fat for gpu placement in the next pcie slot. Others are smaller.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: joshv06 on May 24, 2012, 01:33:08 AM
Could propably be done with water coolers that have their inlets on the top (not like ek on the side)
There are some systems for sli or cf that feature an interconect for 3 or 4 gpus, but as i know these systems are not made for this. They are double wide, leaving a pcie slot free.

I look for a pic

And ek waterblocks are to fat for gpu placement in the next pcie slot. Others are smaller.

Thanks for the reply, like I said, I have seen it discussed everywhere, but all the pictures I have seen have been a 4 way SLI/CF setup with 1 space in between. If anyone finds a water cooling setup with GPUs that have no slot spacing, let me see! :D


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: cncguru on May 24, 2012, 02:50:52 AM
Something like this?


http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg (http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg)


http://dl.dropbox.com/u/71042493/(6).jpg (http://dl.dropbox.com/u/71042493/(6).jpg)


 ;D ;D ;D ;D ;D


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: rjk on May 24, 2012, 03:05:06 AM
Something like this?


http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg (http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg)


http://dl.dropbox.com/u/71042493/(6).jpg (http://dl.dropbox.com/u/71042493/(6).jpg)


 ;D ;D ;D ;D ;D

Daaaaamn that looks sweet. Is it yours? If so, what kind of flow restriction would I expect from something like that? Have you tried them in parallel? And if they aren't yours, let me know whose they are.


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: joshv06 on May 24, 2012, 03:06:16 AM
Something like this?


http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg (http://dl.dropbox.com/u/71042493/(6)gtx580'S.jpg)


http://dl.dropbox.com/u/71042493/(6).jpg (http://dl.dropbox.com/u/71042493/(6).jpg)


 ;D ;D ;D ;D ;D


Omg me gusta :|. How did you do it man? What connectors did you use? What kind of radiator are you using for that!? Looks sick man! Please post all specs :)


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: cncguru on May 24, 2012, 03:12:18 AM


http://dl.dropbox.com/u/71042493/support.jpg (http://dl.dropbox.com/u/71042493/support.jpg)


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: joshv06 on May 24, 2012, 04:17:03 AM


http://dl.dropbox.com/u/71042493/support.jpg (http://dl.dropbox.com/u/71042493/support.jpg)

So how do you connect them side by side?


Title: Re: Would that work? 6x 7970 on Sapphire Pure Black 990FX
Post by: cncguru on May 24, 2012, 04:52:53 AM
The answer is right there in the pic.

Asus P6T7 WS Supercomputer
2- antec 1200's
I-7 990x
12GB Corsair Dominator GT 2000 8-8-8-24


Black manifold with inlet/outlets ties all blocks together nice rigid and compact plus no extra connectors between to possibly leak.
Just wide enough for single slot spacing
Odd 7th card just didn't want to co-operate so was left out.

Have to admit I reverse engineered it though from existing system of a friend of a friend

Been building wacky systems like these for 10yrs before I even heard of bitcoins

All cnc machined of course!

No I do not mine with things like this, way too much extra overhead but I just can't stop building crazy monsters for fun.

 ;D ;D ;D