Litecoin build for noobs: 3x 7950s (1.8 MH/s) in a $10 crate case

[tacotime]

People keep asking me about what to do for their first rig etc. so I'm going to outline it quickly here and make it easy for everyone.

I recommended non-powered (regular) x16 --> x16 extenders and three cards per board.  I've run rigs like this for months on end with no problems (no motherboards frying etc)

Stuff needed: (intel build)
3x pcie x16 motherboard eg http://www.newegg.ca/Product/Product.aspx?Item=N82E16813157295
celeron cpu eg http://www.newegg.ca/Product/Product.aspx?Item=N82E16819116409
8 gb ddr3 ram (2x 4gb) eg http://www.newegg.ca/Product/Product.aspx?Item=N82E16820104262
1 sata hdd eg http://www.newegg.ca/Product/Product.aspx?Item=N82E16822136591
3x non powered x16 extenders from ebay eg http://www.ebay.com/itm/New-PCI-E-Express-x16-Extender-Flexible-Ribbon-Cable-/281070938954?pt=LH_DefaultDomain_0&hash=item4171222b4a
1x wifi adapter (any, usually usb) if needed
gold or platinum 850w psu eg http://www.newegg.ca/Product/Product.aspx?Item=N82E16817139011
3x 7950s (MSI and Sapphire are some of the few non-volt locked ones right now) http://www.newegg.ca/Product/Product.aspx?Item=N82E16814127667

Build is the same for amd, just use a board with 3x pcie x16 slots and a cheap cpu

Then, buy this from home depot:
2x plastic crates
small wood or metal screws that are pointed, about 1.5-2.0 cm long and are small enough to go in the GPU plate holes
2 ft ruler shaped flat piece of steel (they sell this in 4 ft I think, you need to cut them in half with a hack saw)
vinyl stick on cushions http://www.homedepot.ca/product/1-2-clear-vinyl-pads-surface-gard/948073
--> $10 for a case

Put the vinyl cushions on the bottom of one of the crates.  Put the motherboard on top of the cushions.
Put the PSU in the other crate.  Add RAM/CPU.  Hook up the PSU to everything.
Insert the extenders and plug in the hard drive.
Put the cards on, screwing them into the inner lip of the plastic crate and bracing them with the flat piece of metal you bought as a cross member towards the end of the card.
Plug the card into the extender and connect remaining power bits.
Turn rig on by shorting the power pins on the motherboard with a screwdriver, then set the motherboard to turn on as soon as power is given to it ("Wake on power" option in BIOS).
Install Windows (use a USB drive or connect a SATA DVD Drive temporarily), mine (I use guiminer-scrypt).

This is what it looks like:


Rig power consumption at 1.8 MH/s is ~750 watts in summer or ~650 watts in winter.

[1715113878]

1715113878

[1715113878]

1715113878

[1715113878]

1715113878

[1715113878]

1715113878

[1715113878]

1715113878

[Bitcoinassasin]

Great writeup! Thanks for taking the time to write!

[GoldenAngel]

Great thread. Is there any scripts that we need to install? Or is it pretty much,

1. Construct LTC miner
2. Install windows
3. Start mining LTC

[GoldenAngel]

I've also been told to leave the PSU and go for a modular one. What do you think about this? Keeps things less messy.

[elvisrene]

thanks taco looks great .It's what i got so far was looking to add one more card..What do you think.

[tacotime]

thanks taco looks great .It's what i got so far was looking to add one more card..What do you think.

You'll probably need at least one powered extenders.  I hate using them because it tends to make a clusterfuck with all the molex cable, but you're welcome to.

[tacotime]

I've also been told to leave the PSU and go for a modular one. What do you think about this? Keeps things less messy.

It really doesn't matter.  With this build the PSU is in another crate and you can tie up loose cables with cables ties.

[flound1129]

With ~$1350 worth of GPUs in there I'm not really sure why you wouldn't spring for the extra $40 for a proper case...

[wndrbr3d]

With ~$1350 worth of GPUs in there I'm not really sure why you wouldn't spring for the extra $40 for a proper case...

Cooling.

[tacotime]

More Q's I'll post here

Q: All I need to do is just install windows and go from there?
A: Yes, you'll need a temp dvd drive or just install from a USB stick.  I just did this the other day, install windows, the driver + sdk, afterburner, and GUIminer-scrypt and go from there.  You may need to cut holes to put USB devices in, just use a cheap soldering iron.

Q: Would those components be the same if I were going to be running 10 units or would you personally use different equipment to maximize hash power.
What cards would make the units as productive as possible that are still available in large quantities?
A: Personally I would make them all like this.  You can fit a maximum of 7 cards in the rig, but I don't like doing that because that many cards makes a ton of heat right next to the board and will only save you about 70w (most modern mobos and cheap cpus only use ~70w).  Additionally, you need powered extenders for >3 cards and they are also a pain in the ass (molex cables everywhere, bad airflow).  The motherboards you buy have very high resale value so you can always just dump them in a year.

As far as scaling up, you can put two PSUs in a single crate and then put two rigs on either side.  You can then stack the units by cutting out the bottom on some more crates, putting these empty crates on top (the GPUs are above the top of the crate for me so you need to cut out the bottoms), then on top of these crates just install another 3x crates with 2x mobos and 2x PSUs.  
Like this:
### <-- etc
### <-- empty
### <-- 2x mobo, 6x cards, 2x psus
### <-- empty
### <-- 2x mobo, 6x cards, 2x psus
Because of the empty space, there's lots of air circulation and you can easily install 120mm or 200mm fans if you want to to help keep things cool.

Sapphire cards are available in very large quantities at the moment if you can't get MSI or don't want to spend more.

[tacotime]

With ~$1350 worth of GPUs in there I'm not really sure why you wouldn't spring for the extra $40 for a proper case...

Yes, modularity and cooling.  Also these are quicker to build, I can get about 10-20 units up and running in a day if I clone the HDDs.  The crates themselves only cost $2-3.

[elvisrene]

grate idea taco thanks .But i still can get all my gpu's to there full potential ...I'm using 7950 maybe it is the driver from amd catalyst that is giving me problems and those not let me use the reaper.

[efx]

Box fan(s) moves far more CFM than almost any case. Good job, tacotime!

^I suggest cleaning the drivers (I used AMD cleanup utility after using catalyst uninstaller). If you are downgrading your opencl SDK/AMD APP, you may have to remove those specific files from your windows (or whatever) directory. The locations should be in the APP installation notes.


Although it could just be a bad reaper config.

[FullLife]

Very nice guide taco!  I was just wondering, would it be better to use 16x to 1x cable risers instead of 16x to 16x?  You wouldn't need a mobo with all those 16x slots and I'm sure airflow would improve b/c 1x cables are obviously much narrower than 16x cables.

[corbs132]

Don't you think 850w is too small for 3 7950s? i have a 750w for my 2 7950 setup

[AMD FTW]

Not a bad setup for the price. I built mine a year ago and each level was a add on and its all slides on and apart within a minute. Each motherboard tray pulls out to be serviced if it needs. Each level costs about $15-$20 to make. Some cheap thin aluminum angle with a few gussets makes for a decent structure that open exhausts well. You can see the top two levels I added an aluminum bar to screw the video cards into which was a nice addition to the setup. All the other cards are cable tied to the motherboards rails that hold the acrylic plastic.

[AMD FTW]

Don't you think 850w is too small for 3 7950s? i have a 750w for my 2 7950 setup

A good 850w psu can power 4 7950's on an energy efficient cpu setup. I've been running my corsair AX-850 golds like this for a while and have a seasonic gold doing the same.

[corbs132]

Does the amount of 12v rails in the psu matter?

[elvisrene]

Not a bad setup for the price. I built mine a year ago and each level was a add on and its all slides on and apart within a minute. Each motherboard tray pulls out to be serviced if it needs. Each level costs about $15-$20 to make. Some cheap thin aluminum angle with a few gussets makes for a decent structure that open exhausts well. You can see the top two levels I added an aluminum bar to screw the video cards into which was a nice addition to the setup. All the other cards are cable tied to the motherboards rails that hold the acrylic plastic.

Hey men that is cool how many hashs do you do with all those gpus

[Joerii]

Thanks for that noob built. I'm going to try it out ASAP.

Two questions :

1 How about airflow for the mobo ? I've read that there's parts on it that need some airflow to keep them from overheating.

2 Could you elaborate a bit on why using a powered riser is so much hassle ?


I did some math and all the parts for the machine , except for the GPU's,  cost €366.  If you add another GPU you would divide that cost by 4 instead of 3, €91 instead of €122 per GPU. I guess this is not a big enough number to risk frying a rig over though

And I also did not take into account how much more a more powerfull PSU costs. But you could use the same Mobo if you use 4 7950's, right ?