My new mining rig - quad 7970 - Going for 3Gh/s

[bitbrandon]

I think due to the design on these cards there's no good way for me to place the fans. They draw air in from the front, and mostly exhaust through the top leading edge of the card. The heatsink fins run perpendicular to the length of the card, so not much air can make it out the end. The rear of the card does seem to vent a bit, but I'm pretty sure most of it comes out the top or directly inside the case.

I swapped the fans and it's not much better like expected. One card seems to run a tad bit cooler (90 instead of 95), but I still have it slowed way down. The others are all still running at 95 or so, throttling every now and then. I don't much care for the cooler design on these cards!

Thanks for the comments guys!

Edit: I think I might have a problem with the thermal compound on one of these cards. It sure seems to idle higher than the others. Taking the cooler off is going to void my warranty though, isn't it?

I just noticed that the fins are indeed not parallel to the board... stupid design IMO. Also, re-applying the thermal compound is alright with some manufacturers, but I'm not sure if Gigabyte is one of those. *IMPORTANT* If you do apply new thermal compound, please please only apply a super tiny amount. Less = More in this case and considering the GPU chip is less than half the size of a CPU, it should only be around a couple millimeters at most. Let me get a link for you that describes this, but for CPU's. Found it: http://www.hardwaresecrets.com/article/What-is-the-Best-Way-to-Apply-Thermal-Grease-Part-1/1303

[bitbrandon]

I am a CNC Machine Operator for a 3 meter by 1.5 meter sheet at 3mm thick is about $170 You would only use half that for a case.

I am thinking of doing the same as you but main problem is your cards over heating I was thinking of getting the "EVGA X79 Classified" motherboard since it has 3 graphics card slots evenly spreed out a lot of room be twin them.

How much did that setup cost you? I have around 5k to spend and am looking at getting 1 dedicated pc or 2-3 pc's with 3 7950's
What would you guys recommend to do I will be using it just to mine coins.

Thanks, that is really expensive for a sheet... I'm looking for some type of metal that is ~3mm thick that is cheap.

Now, if I were you, I would not blow that much money on a setup. Go for some old ATI cards that are rated really well for M/hashes and throw a bunch of them on a decent motherboard, but not an expensive motherboard like the EVGA one.

[meathelix]

The only way your cards will not over heat is by water cooling them all, All them fans arnt going to do much when your cards are squashed together like that, Since all your fans are doing is trying to force air be twin them in which case wont cool then down much due to the heat they are making is just over powering. It may drop a little bit but not much. Watercooling is the way to go if your cards are like that.

Why I have been told its better to get cheaper rigs with a few cards then it is to spend it all into one big machine. They will mine at the same speed but you wont have heating problems.

[pontiacg5]

I too would not spend that much on a setup. I'd put half into bitcoins, and use the other half to build a rig like mine  

But don't do what I did and buy an expensive motherboard. Go for a cheaper one and use riser cables to make them fit. I'd probably use powered riser cables, just because the cheaper boards aren't designed with 4+ high end cards in mind. If you did it that way you could fit more than 4 cards on a board, meaning less money wasted on cpus and mobos.

2mm thick aluminum would be cheaper and more than sturdy enough for any computer case. Last I checked a 4x10 sheet of 14 gauge aluminum was around $60 bucks. That's right around 2mm, and would also be plenty sturdy. Plus you could have it anodized and it would look wicked cool!

This case is made from 16 gauge stainless which is only like 1.5mm. It's plenty sturdy, so long as you get a few bends into it. I could stand on this one if I wanted, with the corners welded up that is

Meathelix - riser cables would solve the spacing problem, assuming you are using a custom case. Then you could run 4 cards spaced the same as they would be as two on one motherboard. I'm patiently waiting for my riser cables to come. With the extra space between these cards I don't think all these 120mm fans will have a problem keeping them all cool.

I'm even thinking about making some ducting to channel the air directly out of the heatsink... Anything ought to be possible if you can mount them freely!

[meathelix]

Thanks, that is really expensive for a sheet... I'm looking for some type of metal that is ~3mm thick that is cheap.

Now, if I were you, I would not blow that much money on a setup. Go for some old ATI cards that are rated really well for M/hashes and throw a bunch of them on a decent motherboard, but not an expensive motherboard like the EVGA one.

Thing is now days the cards the old cards cost as much as the new ones.

[bitbrandon]

I guess 2mm is fine, I just didn't want some flimsy piece that I could dent by pushing on it with my finger.

[meathelix]

Yea come to think of it 3mm is quite thick So I am still considering if I want to spend so much on mining. People are saying go this way or go that way quite confusing.

But yea riser's would do the job since your cards wont be squashed making it hard for the air to flow through them.

[mccminer]

I'm assuming you spaced yours apart with riser cables right? Are you using the powered version? My motherboard has a sata plug that supposedly adds extra power to the pci-e bus. Won't even boot without it if you've got more than three cards in there. If I wanted to upgrade to a few extra cards would you recommend the powered versions? I wanted to try and run them all on the mobo, but since that isn't possible I might as well add more haha

Are you running the reference clock? If not what sort of clock are you running to get that hashrate? I'd be a bit dissapointed to learn that you were able to generate the same average per card hashrate as I do at a slower clock lol. I might just return these ghz editions and switch to reference cards.

Would I see a gain in hashrate moving to Linux? I assume that the gui kinda takes away from efficiency a bit, right?

Thanks for the post Mccminer!

Mine are actually on two different motherboards.  One unit has 3 cards and the other has 2.  All are connected directly to the motherboards.  Mine is just an open air setup with a good fan blowing across all 5 cards.  I setup a script to monitor my card temps every 15 minutes and log them for me to keep track of, and none of them get over 72C.  I've played around with the core/mem settings quite a bit on my cards and most of them are running at 1150/800, if I remember  correctly (don't have access to my machine right now).  Not sure how much is to gain, if anything from running Linux.  I just used it because I like it, it's free, and I don't have a copy of Win7 laying around. 

[degart]

WOW nice setup !

[TriplD]

Do we all agree that this rig at 3Gh/s would net about 55 Bitcoins in a year at a 2% difficulty per month increase?...according to the calculator I used.

So, an approx. $2500 investment would bring back about $7500 in a year at $136 price of Bitcoin at the time of this post?

Is this how the math should work?

A true Newbie question.....

[mxmz.in]

Do we all agree that this rig at 3Gh/s would net about 55 Bitcoins in a year at a 2% difficulty per month increase?...according to the calculator I used.

So, an approx. $2500 investment would bring back about $7500 in a year at $136 price of Bitcoin at the time of this post?

Is this how the math should work?

A true Newbie question.....

Minus electricity

[FTWbitcoinFTW]

at a 2% difficulty per month increase?

Good luck with that...

Expect x10 to x30 in the next 12 month

[grinandbearit]

nice setup!

how much money did you spend on it?

[pontiacg5]

Mine are actually on two different motherboards.  One unit has 3 cards and the other has 2.  All are connected directly to the motherboards.  Mine is just an open air setup with a good fan blowing across all 5 cards.  I setup a script to monitor my card temps every 15 minutes and log them for me to keep track of, and none of them get over 72C.  I've played around with the core/mem settings quite a bit on my cards and most of them are running at 1150/800, if I remember  correctly (don't have access to my machine right now).  Not sure how much is to gain, if anything from running Linux.  I just used it because I like it, it's free, and I don't have a copy of Win7 laying around.  

The card I've got in open air manages to stay around 75 degrees, but that's at 1175. I can't seem to get windows to take anything less than 1500 for a memory clock, I can try and set it in CGminer and I get a confirmation that the driver reported success or something, but it resets back to 1500 or never changes in the first place. I'm going to have to look into that a bit once the heat is under control!

I bought a bunch of off lease PCs a while back for work, a couple are just lying around as spares so I borrowed the refurbished keys. Don't tell Microsoft!

Degart - Thanks!

TriplD- I'm expecting this thing to pay for itself in a little over three months. I'm not expecting GPU mining to be profitable for much longer, either BFL will finally deliver or someone else will. Either way, my already insignificant % of network hash rate will become even more insignificant!

I'm thinking of preordering a few BFL bits too. Least I can physically drive over there and kick some butt if they don't deliver. Only like 20 minutes away from me!

Mxmz.in - Power is free for me as I'm running this thing at work. I manage all the computers across the shop so this one is just going to blend in. With as much power as we use (three phase too!) we get it pretty cheap anyway.

This thing managed to crank my living room temperature up to around 85 degrees in the three or four hours I had it going last night. NOT cool, at all! That alone is reason enough not to run it at home to me lol

Edit:

Grinandbearit - I've got about $2500 in this one, not counting the stainless sheet or any labor/machine time going into making it. I did all that on my own, so I consider that free. My time is worthless I guess haha 

[Paya]

Impressive machinery 

[TriplD]

Expect x10 to x30 in the next 12 month

My point is that this just doesn't seem to be a great investment. All the time people on this board are putting into mining questions and only some are actually mining, the time investment alone is prohibitive for me even considering getting in. Money is no object for me, but I can't buy the expensive rigs (Avalon and BFL) - certainly not going to give them my money with such a poor track record...there are better investments.

I'm not expecting GPU mining to be profitable for much longer

No kidding....

Grinandbearit - I've got about $2500 in this one, not counting the stainless sheet or any labor/machine time going into making it. I did all that on my own, so I consider that free. My time is worthless I guess haha 

If you had put that $2500 into Bitcoins a couple weeks ago when it declined so much...your would have doubled your money by today's price. Then you just sit and wait for Bitcoins to hit $500 each...or more...if you firmly believe it will.  Think of the babysitting you do with your rig...Bitcoins in a wallet require no commitment. 90% silver or 1/10th gold coins don't either. Perfect time to buy precious metals is now. Mining seems to be a humongous waste of time.

[Pt0x]

Great setup!

[Pt0x]

Do we all agree that this rig at 3Gh/s would net about 55 Bitcoins in a year at a 2% difficulty per month increase?...according to the calculator I used.

So, an approx. $2500 investment would bring back about $7500 in a year at $136 price of Bitcoin at the time of this post?

Is this how the math should work?

A true Newbie question.....

can you share the link of the calculator?

[FTWbitcoinFTW]

http://blockchained.com/profit/
https://bitclockers.com/calc
http://www.bitcoinx.com/profit/
http://dustcoin.com/mining

[sheepson]

Looks awesome!