5970 Cooling Solutions

[Cablesaurus]

I have never heard of voltage stepping explained like that and you just made my life much easier lol! Much easier to test and troubleshoot if I have a meter to go on like that. A BIG THANKS to you, and everyone, for the assistance so far.

[Cablesaurus]

Well, I thoroughly tested both of my cores. One does great and the other is horrible!

On the better core, I can sit at a fairly comfortable 76-78c steady with ~98-102c vrm @ 1.1500v @ 950mhz, which brings that core from 270,000khash/s to 350,000khash/s.

While that's really nice, the 2nd core just doesn't hold up to much voltage increase, even stepping up to 1.0750 or 1.1000 @ 800 or 850mhz starts pushing temps on everything up without steadying out.

Not sure at this point if it's worth it to continue overclocking on this machine, that's about 60-80k khash which is maybe a block or two a month. That'd be a nice addition but at the same time running the fan @ 100% (which happens to be my workstation), as opposed to being able to have it at 70% otherwise is a little easier on my ears. Not sure.

[sc8nt4u]

Well, I thoroughly tested both of my cores. One does great and the other is horrible!

On the better core, I can sit at a fairly comfortable 76-78c steady with ~98-102c vrm @ 1.1500v @ 950mhz, which brings that core from 270,000khash/s to 350,000khash/s.

While that's really nice, the 2nd core just doesn't hold up to much voltage increase, even stepping up to 1.0750 or 1.1000 @ 800 or 850mhz starts pushing temps on everything up without steadying out.

Not sure at this point if it's worth it to continue overclocking on this machine, that's about 60-80k khash which is maybe a block or two a month. That'd be a nice addition but at the same time running the fan @ 100% (which happens to be my workstation), as opposed to being able to have it at 70% otherwise is a little easier on my ears. Not sure.

Sounds good . You might be breaking even with the machine with 60-80k in terms of electricity costs probably.

[dingus]

I have only just skimmed through this thread so forgive me if this has been said, but I would like to add that if I underclock memory to its lowest clock (in MSI afterburner) it shaves off a few degrees of heat, without losing any hashes/second.

[brocktice]

I am water cooling 3 5970s with a single 3x120mm radiator. I'm overvolting/overclocking to around 925-950 (varies per GPU). I was doing 1GHz, but when I added a third 5970 the power and heat requirements overwhelmed the system. My core temps are 59-69C.

If you want to water cool, you'll probably have to wait for 6990s. Nobody's making water blocks for 5970s, I got the last one I could find recently. I'll post pics/YouTube video in a moment.

[brocktice]

Thank you for the concise response. Do you (or anyone reading) have experience with the water cooling solutions to know which might be best? I have never done a water cooling setup before, but honestly the fan in this GPU is so loud, it would be a welcome change.

I wish I would have known about BitCoin about 3 months ago when I first purchased the card!

Here we go:

http://www.youtube.com/watch?v=zcYuxRde-30

And here's a pic if you don't like YouTube/videos.


Water cooled bitcoin miner, 3 5970s. by brocktice, on Flickr

It was about $500 for the water cooling parts, but it lets me overclock more, and more quietly, since it sits right next to my desk. I figure over time I get a better return from hardware, especially given my power and sound requirements.

[sc8nt4u]

Hey Brock, I noticed that you're using 3x5970s and it looks like your mobo is out of PCI-E slots. Is this the reason you have 3 and not 4? I only have 3 PCI-E slots and 2x5970s right now, but would like to stab another 5970 in there and get it on linux because windows is limited to 2x5970s(?). That's an interesting way to mount a hard drive .

What software are you using to increase your volts in linux or did you use something like RBE to flash to bios to get the clocks and volts you want.

[brocktice]

Hey Brock, I noticed that you're using 3x5970s and it looks like your mobo is out of PCI-E slots. Is this the reason you have 3 and not 4? I only have 3 PCI-E slots and 2x5970s right now, but would like to stab another 5970 in there and get it on linux because windows is limited to 2x5970s(?). That's an interesting way to mount a hard drive .

What software are you using to increase your volts in linux or did you use something like RBE to flash to bios to get the clocks and volts you want.

I have one more motherboard PCI-E slot, but it's too close to the other one so the last 5970 ('bottom' on the pic) blocks it.

The case is a 4u rackmount case, and it turns out there are no 4u rackmount cases with 8 card slot spaces, so without modding them down to only take 1 slot each, 4 cards is impossible in my setup. I also don't have the power supply capacity. If I wanted to go for 4/motherboard I'd do something like Art's custom cases.

For voltage, I'm using rbe and atiflash. No need to change the clocks, just the core voltages.

[brocktice]

That's an interesting way to mount a hard drive .

Both of my 4u rackmount cases came with hard drive cages on a crossbar like that, I didn't come up with it. I had to rip out all the drive bays to fit in the water cooling equipment, so that's the only place left.

[sc8nt4u]

That's an interesting way to mount a hard drive .

Both of my 4u rackmount cases came with hard drive cages on a crossbar like that, I didn't come up with it. I had to rip out all the drive bays to fit in the water cooling equipment, so that's the only place left.

Ah I see, I guess I'll have to try to find another 5970 then. I have a 1250w PSU only, so I think 3 5970s is about as much as it can handle without wiring a secondary PSU in. I'll go look at watercooling stuff now and see if I want to drop that much.

[brocktice]

Ah I see, I guess I'll have to try to find another 5970 then. I have a 1250w PSU only, so I think 3 5970s is about as much as it can handle without wiring a secondary PSU in. I'll go look at watercooling stuff now and see if I want to drop that much.

1250 is going to be just barely enough for 3 if you are overvolting/clocking.

[sc8nt4u]

Ah I see, I guess I'll have to try to find another 5970 then. I have a 1250w PSU only, so I think 3 5970s is about as much as it can handle without wiring a secondary PSU in. I'll go look at watercooling stuff now and see if I want to drop that much.

1250 is going to be just barely enough for 3 if you are overvolting/clocking.

I know. I'm probably going to underclock my CPU. I'm thinking the 3x5970s are going to be pushing close to 1100w or 92A on my 12V rail.

[sc8nt4u]

It's one of those 4U cases marketed by Compucase  and Codegen. All my gpu's are housed in those, but with air cooling. Nice cases, sturdy and simple and that top bar is very useful. 70-100£ each in UK

Mine is all cluttered in a HAF 932  w/ 6 hard drives too + 2 dvd drives.

[brocktice]

It's one of those 4U cases marketed by Compucase  and Codegen. All my gpu's are housed in those, but with air cooling. Nice cases, sturdy and simple and that top bar is very useful. 70-100£ each in UK

My workstation is in one that looks just like it, but from Rosewill. Those aren't sold anymore, which is too bad, because they're nicer.

[Cryptoman]

I don't see the logic of trying to cram more than two 5970s in a box.  The theory is that you only have to pay for one PSU, one case, one mobo, one HDD, etc.  However, your cost per watt for power supplies goes way up above 800-1000W.  Then, if your PSU takes a dump you have 3-4 GPUs offline.  Also, there aren't many 4 PCIe mobos or cases to hold them.  On the other hand, you can get a nice MSI 870-G45 mobo that has two PCIe slots with airspace between them for 70 USD.  Toss that in a garden-variety bottom-PSU mid tower with a nice fan and 1000W PSU and you're golden.  Overclock until the cows come home and it still runs cool.  Am I wrong?

[Cablesaurus]

Can anyone offer a little bit of input on what temperatures are considered "safe"?

i.e., is there a huge difference in stability (or anything to consider) having a stable 78c core/100c VRM, vs. a higher, 82c core/105c VRM?

[ShadowOfHarbringer]

If you want a really professional cooling, you should start building something like this:

http://www.pugetsystems.com/submerged.php
http://www.youtube.com/watch?v=PtufuXLvOok

Easiest to maintain, easy to cool (just make a loop with a pump and add a radiator from a car to it).

I planned to do something like this myself, if only i had the cash.