It's Open Hardware Monitor [openhardwaremonitor.org] - I tried tons of different apps and gadgets and found that to be the best.  It's very customizable, and free to boot.

I'm getting about 48-49C under full load with the fans turned down as low as they go; the pump hums a little louder than all the fans, so I'm definitely happy with that.  It's not silent, but it's pretty damn quiet

[edit] Actually the loudest thing in the rig: the kill-coil bouncing around the reservoir now and again

Looking much better now after redoing the GPU blocks.

I've been running prime95 torture, and two instances of guiminer for about 2 hours now:



This is with all the fans on high, so a grain of salt there, I'll mostly be running this with the fans turned down to a comfortable level, though it's really not too loud on full.

Water cooling is amazing, I should've done this ages ago!

Now the question is.. blue or red Mayhem dye?

Things did not go so well when I booted up - my first GPU was not making contact apparently and soared to 110C idle, shutting off completely within about 15 seconds.  I may have busted this card while troubleshooting.

The second wasn't making good contact, but was holding around 60C idle.

By comparison, my Phenom II 1090T was 28C idle for the short time I got to monitor it.


I highly recommend against the Koolance full-coverage blocks, at least for my combination.

While there is no full-coverage block for non-reference 6950s, the PCB design for reference 6870s is exactly the same as the XFX 6950s I've got, short one mounting hole.  All the VRM, ram, etc are in exactly the right spots.

The Koolance 6870 blocks I got are crap, however, as far as I can tell.  The mounting spacers don't line up properly with all the holes; 5 out of 9 mounts line up perfectly, the others are off by only a millimeter or so, but just enough prevent proper mounting.

On the stock heatsink the 4 mounting spacers around the GPU are flush with the top of the PCB (chip side), and XFX uses screws with springs that 'push through' to keep pressure on the GPU plate.  The Koolance block, on the other hand, has spacers that are flush with the *bottom* of the PCB, so the springed screws I have apply no pressure at all, hence the temperature fail.  Koolance does not supply any screws for these 4 mounting holes, even though they're the most important.

I had to drain my loop and re-do both GPU blocks, adding some washers to get better pressure between the GPU and the cooling plate, and I'm now leak testing again.  Hopefully it goes better this time around.

Unfortunately it was pretty difficult to find reviews for any of the 6870 waterblocks so comparison was hard when I picked them up; I went with the slightly more expensive Koolance blocks versus the 'cheap' WaterCooling blocks, figuring a more well-known brand and higher price would indicate better quality.  Lesson learned.


[edit]  While I was at it, I also replaced that awful tube between the GPU blocks and the reservoir - I had made it longer with the intention of being able to move the reservoir in and out of the case for filling, since it's mounted at the top.  Turns out this was applying uneven pressure at the GPU fitting, and it was starting to slip pretty badly.  I shortened it up almost 2" (!!) and it's much better now, and I can still move the reservoir easily.  I'm learning lots of lessons from this endeavor

Yes it is possible, but you'd need to leak test again after hooking it all up anyway, so why not go in running.

The only component that's powered on right now is the pump, so if it did happen to leak it wouldn't be the end of the world, I'd simply have to correct the problem and wait for it to dry out.

But after about 14 hours it's still leak free, so I think I'm good to go

Lots of progress yesterday!

Mounted all the blocks and cut out some of the harddrive bay wall to fit the pump:




Then I drilled a hole in the case wall where the radiator is mounted for the fan wires.  Here's a protip:

Keep all power tools 10' away from your radiator.

I feel so foolish looking back on it now, I had a bit of a mishap with the drill:



I was being "ever so careful", but I destroyed a few fins and nicked the water channel with the slightest misstep. 

Thankfully I was able to repair the hole with a little bit of solder, and it's now watertight again.  It's a good thing the radiator is so large, I don't think the missing fins will effect performance much if at all, though restricted flow through the patched channel may just a little.

After that little fiasco, I got all the tubing connected, and it's now leak testing and bleeding!



I can't wait to fire it up

It's an el cheapo Sunbeam: http://www.newegg.com/Product/Product.aspx?Item=N82E16811998808

It's 20W per channel, 4 channels, and I've got 3 fans spliced together on a channel.  It does what it needs to do for now but I'll be looking for a better one soon, and/or modifying this one with better components.

The starting voltage for the yate loons is a little high, so if the controller is turned down too low on power-up they don't all spin up.  I can just crank the knobs up a bit to get them spinning, then adjust them down where they need to be, but it'd be nice knowing all my fans are spinning without having to check.

I'm also testing with a small (12V @ 1500mA) external power supply, which could be the culprit since it technically doesn't push enough current to power all 9 fans.  It may be a totally different story connected to the real PSU.

[edit] External power supply wasn't the problem, same thing happens hooked up to my internal.  Appears the fan controller just doesn't supply a high enough voltage at low - I have about 75% of the dial range to play with still, so no huge deal really.

Yate Loons are for the win.



Even with all 9 fans spinning at full it's still 90% quieter than it was before.  Turned down low it's just barely audible, the wifey couldn't tell they were on until she saw them spinning

I managed to save the work I did mounting the rad to the side panel with a little ghetto wooden stand, it's rock solid now and keeps the case off the ground an extra 3/4" to boot.

Also got all the water blocks mounted, tomorrow is modding the case to mount the pump in a reasonable spot, and getting it all plumbed up.  Hoping to leak-test tomorrow night

Hah, yeah, 'Great Value' indeed.  I was a bit worried that it'd be crap honestly, but I figured if I started to see a lot of mineral deposit I'd flush it all and double-distill my own.  Good to know it's not just a fancy label.

I modified the side panel of my case to mount the radiator last night, and it was total fail.  Whole rig toppled over on it's side as soon as I let go  

I'm guessing it's going to be somewhere around 10lbs or so once it's full of water and all the fans are attached, so off to the hardware store I go to rig a radiator stand.

Hooray for the interwebs, everything I need to water cool delivered to my door:




Here's a shot to show just how ridiculously huge the radiator is:




After much fighting with the DVI header on my scrap card, I've decided it's not worthwhile to risk the 6950s.  I managed to get it detached, but it was not pretty at all, and I'm fairly sure I damaged a couple of the traces in the process.

Instead I think I'll be going tri-fire instead of quad, trading my mobo for another with the 16x slots in a better arrangement, and selling off my spare 6950 to pick up the new mobo + 3rd water block.

I've you've got a decent craft/fabric store nearby, sewing machine oil works really well.

I've also used hair-clipper oil, it's basically the same stuff.

Ideally you want something synthetic, organic oils (veggie or olive oil) are generally short lived.

Yes, these are the things that AMD/ATI cards have a great abundance of, which make them better at mining.

I'd be curious to see if he sees any difference between 2, 3 or 4 of those cards, from the research I've done SLI doesn't really give significant gains past two cards. 

I get very near double performance with two 6950's crossfired, however.

Indeed, but the OP never stipulated anything other than 'a few months', is that more than 3 months?  Fewer than 9?

Just throwing figures out like everyone else  

OP needs to actually do the math to see whether or not it's worthwhile, we can bark at the fence all we want otherwise.

Until the hardware is paid off.. the break-even in your image is 96 days, after that's it's pure profit.

But $400 is going to get you more like 600mh/s.

A pair of 5970s would get you to about 1.4-1.5gh/s, but they're on average $400 each.

I'd budget maybe $250 for the mobo, ram, cpu, and PSU.  You're looking at more like $1050 for the system..

Long and short is even with free power it'll be a while before you've paid off the hardware at current difficulty & price, but depending on how long you want to leave it running you could eventually make a profit.

6990M has 1120 stream processors - you're going to see performance roughly equal to, possibly significantly less than a 5830/6870.

You're also going to constantly hit thermal ceiling trying to mine with a laptop.

Basically you'll be paying upward of $1500-2000 for a laptop that doesn't perform as well as a card you can get for $80 on eBay. 

As for noise, the rather tiny fan spinning at a relatively high RPM will tend to whine like a banshee.  It may be 'quieter' than the desktop card, but it'll probably be a far more annoying noise.

An example of 'bad sag' - I had a 450W diablotek (avoid!) PSU who's 12V rail sagged to 10.4V powering just a 35W celeron and a single 5830.  I turned it off immediately and thanked the gods it hadn't fried anything up yet.

Anything >11.5V I'd consider perfectly acceptable on a 12V rail, so yours isn't bad.  I was getting 11.8V or so on a nice Corsair 750W running 3 cards.



Nah the 'same kind of thing' i was referring to was the voltage sag.  Basically, like a chain, the weakest point in a circuit is going to burn out when over-current.  In m3sh3aD's unfortunate case it was his ATX header, was thinking in yours it was the molex plug.

Appears the majority of the damage happened on the edge of the 20pin connector.  It also looks like the plastic shroud around the pin got left behind in the motherboard header, though it's hard to tell from the blurrycam.  It doesn't seem like coming-loose caused it.

I tried to find some info on those Akasa PSUs, they seem to be good little buggers, and definitely have short-circuit protection, so that's also unlikely.

With only 4 cards, and only 3 possibly pulling from the ATX header directly, the only thing that makes sense to me is a serious voltage sag.  If the 12V rail somehow dipped way under spec, the current needed to compensate would have increased greatly, which could definitely lead to this kind of failure while possibly missing the short-circuit protection.

That kind of thing doesn't normally happen without really excessive draw though, so this is a bit of a mystery.

[edit] This thread got way off track   P4man, the same kind of thing could blow the pins in a 4pin molex connector for the same reason, have you measured the voltage on your 12V rails to see if you've got bad sag?

Considering what your boss may be willing to lay down for power costs, perhaps you might want to look at FPGA solutions instead - low heat, low power, but higher upfront costs. 

A 'few months' of powering ~180W 5830s could easily pay for a couple of the available solutions floating around the boards that only pull ~10W.

This is kind of a prime example for the argument that 'free power is never free - someone pays for it', since you actually interact with that someone it may be worthwhile to, you know, not suck them dry.

1) Keeping hardware costs in mind, maybe a HAF-932 is overkill

2) 5830s are noisy and hot.  6 of them will warm up any room, and will not handle an enclosed space well.  If you can't vent in cool air / vent out hot air, 6 of just about any cards are too many.

3) Look at eg. 5770/6770 instead - they're relatively low power (100W?) and produce a decent hashrate (~180-200MH/s), pretty close to a 2 MH/w ratio.  This doesn't matter as much since your power will be free, but lower power usage = less heat, so efficiency is a real concern here too.


To give some perspective, I ran 4x 5830 and 4x6950 in my basement in a well ventilated room, pulling *cold* air in from outside - even when the outside temps were 35-40F, they heated my entire house, to the point I often had to open more windows.

[edit] Additionally, make sure your boss understands exactly how much power is in question here - a rig with 6x 5830 is going to draw about 1-1.2KW at the wall.  Sapping free power for bitcoins probably isn't worth your job

Please tell me you're not using that blown 24pin ATX connector to power another board?

The damage on the board looks like a short, considering the plastic around the pin of your PSU's connector seems to have been left behind.  It would appear that something connected your 12V rail to ground at low resistance.. stray wire around your PCI-e ports or something similar.

If you're still using that PSU with the busted connector.. stop.  That's just asking to start a fire and/or destroy another board.

[edit] I suppose if you're using it to only power the 4 cards directly, and not using that 24pin connector it's probably ok, as long as no +V got got spot-welded to a G when it blew