This machine is being built for the single purpose of mining LiteCoin and other Altcoin Cryptocurrency as efficiently as possible. It is running a Linux distribution on a USB flash drive known as PiMP (Portable Instant Mining Platform) – see below for more information.
Current version of PiMP on this rig is producing about 700kh/s (kilohashes per second) per card at 75C with a minor overclock and a BIOS hack to reduce voltage from 1.175v to 1.25v!! See screenshot below.
Before we begin I would like to give a ton of credit to my friends in #PiMP on FreeNode IRC, for helping and inspiring me with this project. I can be reached on FreeNode at melt7777.
First things first, we needed a board, processor, ram, and a good air-efficient case.
The low-priced, power-sipping, single-core AMD Sempron 145 is a 2.8GHz retail boxed processfor for about $30. It will not be used for much, so it’s more than enough.
The ASRock 970 Extreme4 AM3+ 970 ATX AMD Motherboard is an inexpensive board that has a socket for our cheapie AMD CPU but can always take a real AM3-socket CPU if we want to use this board on a normal (non-mining) machine. It will actually make an effective gaming PC board as it has all of the modern features found in today’s motherboards. Specifically it has three PCI-Express x16 slots with SLI/CrossfireX support. While we will not be activating the Crossfire for mining, it is nice to have for a future gaming PC. Now, I am a big fan of the ASUS boards, and I have the ASUS Z87-PRO running my overclocked i7-4770K in my main rig overclocked smoothly. So we get the same quality of ASUS in the ASrock, they are a sub-company or whatever. And the reviews are excellent.
Most mining rigs are recommending 2x2GB RAM, as it is cheapest, but I chose to go with 2x4GB simply because the 4GB chips will be more useful for repurposing or resale and I found it to be a better investment. I chose the Crucial Ballistix Sport 8GB DDR3-1600 PC3-12800 because I have had good success with the Ballistix series and they receive good reviews and good pricing. Also, they look cool.
A Big old Milk Crate – free!
Very important to have your power sufficient and efficient. I paid the extra for a PSU that’s built Ford tough, gets great reviews, has all of the connections and cables, and is Platinum efficient. Nearly all of the 1000W Platinum and Gold rated supplies have about 85-90 Amps on the 12v+ rail, which will be enough current for my 3 GPUs and the board. The EVGA SuperNOVA 1000P2 1000 Watt Full Modular ATX Power supply was also on a $15 rebate at the time, so that was icing on the cake!
GPUs (Video Cards)
And now for the guests of honor… I spent a considerable time researching the various cards, hashrates, prices, and ROI. No matter which cards I chose I came to the conclusion that the return on the investment of the GPUs would be approximately 4-5 months if the LTC-USD value stayed the same, around $20 per LTC, and averaging the current and next difficulty levels to be conservative.
I ended up choosing three XFX AMD Radeon HD 7970 Double D 925MHz 3GB cards.
USB Flash Drive
MicroCenter 32GB USB 3.0 are quality drives at a very low price. Reliable and convenient. This will be running our Live Linux OS.
PCI Express Riser Cables
To get these cards up off the motherboard and properly cooled, I purchased three PCI-Express x1 to x16 Powered Risers. These are ribbon cables that allow the GPUs some room to breathe. Power comes in through a Molex pigtail to power the GPU fans directly from the PSU.
PiMP – http://getPiMP.org
For More Information about LiteCoins, Mining, and the Calculations used in this build, check out the following:
Litecoin Mining Calculator (Hash rate, difficulty, and fee -> LTC Mined per day/week/year):
LiteCoin to USD Exchange Rate Calculator:
The LTC to USD Exchange Chart from BTC-e Exchange:
Hardware Profitability Charts:
An example of a Litecoin Mining pool that I use (Allows mining of all Bit and Alt Coins or the Multi-Port which auto-switches to the most profitable coin at the moment. Also allows automatic daily payouts and a DDoS-protected stratum server!):
An example of Currency Exchanges used to accept pool payouts and convert and trade currencies:
Internet Relay Chat (IRC Channels) on irc.freenode.org:
#PiMP, #litecoin, #litecoin-bamt, ##ipominer, #multipool, #sgminer
SGMiner Configuration for XFX AMD Radeon 7970:
root@jcminer1:/etc/bamt# cat cgminer.conf
“pools” : [
“url” : “stratum+tcp://poolname:7777”,
“user” : “username.workername”,
“pass” : “x”
“auto-fan” : true,
“intensity” : “19”,
“vectors” : “1”,
“worksize” : “256”,
“kernel” : “scrypt”,
“lookup-gap” : “2”,
“thread-concurrency” : “40960”,
“shaders” : “0”,
“api-listen” : true,
“api-port” : “4028”,
“api-allow” : “W:127.0.0.1”,
“expiry” : “120”,
“gpu-dyninterval” : “7”,
“gpu-platform” : “0”,
“gpu-threads” : “0”,
“gpu-engine” : “1100”,
“gpu-memclock” : “1625”,
“gpu-powertune” : “20”,
“log” : “5”,
“no-pool-disable” : true,
“queue” : “1”,
“scan-time” : “60”,
“scrypt” : true,
“shares” : “0”,
“kernel-path” : “/usr/local/bin”,
“kernel” : “ckolivas”
With the help of MonkeyToe, VBE7, and the litecointalk forums, I have been able to reduce the operating voltage of my video cards from 1.175v to 1.125v. This allowed to bring the core clocks up to 1054 from a previous 957. Hashrate has increased from 650kH/s to 690kH/s with temps of 75C and total reduction of 35W power use for the rig!
melt7777 in the Mining Community
melt7777 is the founder and project team leader for the latest and greatest mining operating system, PiMP, the Portable Instant Mining Platform. More information can be found at the website http://getPiMP.org where he manages the FAQ, Changelog, Bug Report ticket system, and provides IRC support in the #PiMP irc channel along with lead developers lily and sling00.
melt7777 provides support in the #litecoin-bamt support channel as well as on various forums and helping maintain the BAMT support wikia: http://bamt.wikia.com
melt7777 has been a lead developer in the latest iteration of the hit mining operating system, BAMT (Big A Miner Thing). With 2.0.1 beta release under his belt, a complete rebuild from the ground up, he continues to work with the testers and community to refine and upgrade the capabilities of this operating system.
melt7777 has played a large part in developing the new BAMT 2.0 release as well as contributions to lily’s Linux-PoolManager especially in the theme features and testing. The latest PoolManager software can be found at : https://github.com/starlilyth/Linux-PoolManager