Cryptocurrency Mining

This post is a walk down memory lane of the past two months of mining.

Smashing 4 GPUs together doesn't work well at all without hardcore ducting. Turns out that this setup actually mines slower than 3 GPUs and a fan on top.

It turns out that the limiting factor is power density. I wasn't going to buy faster GPUs because of a poorer hashrate per dollar, so I needed to get more PCIe slots. I bought some dumb nodes to get my other pile of GPUs up, but after this fan cutting my hand (and losing a blade in the process), I resigned.

Pile of unused GPUs. These sat unused for the duration of mining.

My two former miners:

tl;dr Making money is hard.

The Nicest Balls You Will Ever See

My CUDA Ray Tracer works! Now to make it photon map…

12 Days of Christmas

Sung to the melody of Twelve Days of Christmas

On the first day of Christmas
My true love sent to me
a OneTesla coil

On the second day of Christmas
My true love sent to me
Two PSUs
and a OneTesla coil

On the third day of Chirstmas
My true love sent to me
Three mannequins
Two PSUs
and a OneTesla coil

On the fourth day of Christmas
My true love sent to me
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the fifth day of Christmas
My true love sent to me
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the sixth day of Christmas
My true love sent to me
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the seventh day of Christmas
My true love sent to me
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the eighth day of Christmas
My true love sent to me
Eight processors
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the ninth day of Christmas
My true love sent to me
Nine monitors
Eight processors
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the tenth day of Christmas
My true love sent to me
Ten SSDs
Nine monitors
Eight processors
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the eleventh day of Christmas
My true love sent to me
Eleven bugs to fix
Ten SSDs
Nine monitors
Eight processors
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

On the twelfth day of Christmas
My true love sent to me
Twelve sticks of RAM
Eleven bugs to fix
Ten SSDs
Nine monitors
Eight processors
Seven ballcopters
Six hamburgers
Five KawaiiKarts
Four GPUs
Three mannequins
Two PSUs
and a OneTesla coil

Achievement Unlocked: GPU Insanity

You are looking at two gorgeous eVGA GTX 460 2Wins, which are eVGA's attempt at the dual GPU thing. I nearly had a shortage of 8-pin connectors (there's only two on this power supply), but was solved by using a dual 6-pin to 8-pin adapter (and then I almost ran out of 6-pin connectors -- go figure). My test cuda code verifies that I indeed have four GPUs:

shewu@hamburger ~/Dropbox/Projects/cuda
 % ./getgpu 
This computer has 4 GPUs
CUDA device #0
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #1
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #2
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #3
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz

If you're interested in the code, here it is:

#include <iostream>
#include <cuda.h>

using namespace std;

void printDeviceProp(cudaDeviceProp& devProp_)
{
        cout << "Name: " << devProp_.name << "\n";
        cout << "Total memory: " << (devProp_.totalGlobalMem/(1024*1024)+1) << "MiB\n";
        cout << "Clock rate: " << devProp_.clockRate/1000 << "MHz\n";
        return;
}

int main()
{
        int devCount;
        cudaGetDeviceCount(&devCount);
        cout << "This computer has " << devCount << " GPUs\n";

        for (int i = 0; i < devCount; ++i)
        {
                cout << "CUDA device #" << i << "\n";
                cudaDeviceProp devProp;
                cudaGetDeviceProperties(&devProp, i);
                printDeviceProp(devProp);
        }

        return 0;
}

Sad to say that I still can't tell Bayley to eat my dust just yet.

I love you EVGA

The Nvidia-only GPU and motherboard manufacturer has the best customer service ever!

Remember the GTX 460 2Win I got from eBay? It stopped working a couple of weeks later. I instinctively opened an RMA request on EVGA's website and mailed the defective card in, only realizing after I dropped it off at USPS that the warranty-is-void sticker was removed! I panicked and prayed that EVGA would be nice and send me a replacement anyway.

Less than a week later, EVGA calls me, but I didn't pick up since my 6.02 exam was about to start (literally). A couple days later I receive email from EVGA that a replacement is coming my way! I checked the serial number and it indeed is not that of the one I sent in! Woo!

I finally took the time today to retrieve it from desk and test it. After booting my computer with my 30" plugged into the unit, I got a black screen, so I rebooted the machine. No luck. I then installed my 8800GTS (another EVGA card), plugged the 30" into that, and the machine booted with video. It's a bummer that the card has issues driving my 30", but I bought it for compute, so no worries.

I'm convinced that EVGA was nice only because I mentioned that I have an SR-2 in the RMA request.

Here's to two more?