Category Archives: Guides

Undervolting in Linux via modified video BIOS


Before VBE7: Creating custom vBIOS files meant manually editing hex and hoping for the best—yuck!

For a long time, I’ve held off on writing a guide about modifying your video BIOS for the purpose of lowering voltage. Undervolting has the potential to reduce power draw by about 50 watts per GPU, so it’s easy to understand the appeal—you’ll see a significant savings on your electricity bill if you’re running a 3×7950 rig (like the one in my guide) 24/7. Unfortunately, the AMD Radeon drivers in linux don’t allow voltage control, so the only current way to lower voltage below manufacturer-specified levels in linux is to modify your video card’s BIOS.

In the past, such a hack involved manually editing your vBIOS file by hand, using a hex editor. Most folks hesitate to make such a modification, as performing the edit can be tricky if you’re not familiar with hexadecimal—and a mistake can mean a bricked GPU. Due to the potential danger I had decided not to post a guide about manually modifying your vBIOS ROMs. After all, nobody wants to be left with a $300 paperweight after inadvertently trashing their video card.

Enter VBE7, a GUI-based vBIOS editor for Radeon 7xxx series GPUs. Now anyone can easily make changes to their vBIOS without having to muddle around in a hex editor, praying they get things right. I’ve been testing VBE7 for a few days now, and it appears to work brilliantly. Read on for my guide on creating your own custom power-saving vBIOS!

Guide: Cryptocurrency Wallet Security

Litecoin walletSo you’ve built your own mining rig, you’ve mastered the art of trading for profit on the cryptocurrency exchanges, but you haven’t given much thought to securing your digital fortune against theft and accidental loss? Don’t worry, you’re not alone. Wallet security isn’t exactly a glamorous topic. In fact, many of you might even assume that you don’t need your own wallet at allafter all, mining pools and currency exchanges are more than happy to hold your money for you, right?

Letting somebody else control your money is a mistake that will likely end up costing you at some point. That mining pool operator that you assume is trustworthy could very well be a teenager halfway around the world that has no problem stealing your coins. The various digital currency exchanges are unregulated, not necessarily secure, and a daily target for hackersgood luck getting your money back when one is breached or goes belly up.

Since it’s still basically the Wild West when it comes to cryptocurrencies, the only way to ensure that your digital wallet can’t be stolen or lost is to secure it yourself. Thankfully, this isn’t all that difficult if you follow a few basic rules. Read on for the guide.

Build your own Litecoin Mining Rig, part 5: Mining FAQ

In this fifth and final installment of our litecoin mining rig guide, I’ll answer some common questions about building your own rig, profit expectations, and mining in general. If you’ve read the rest of the guide and still have some lingering questions, you might find the answers you’re looking for here.

Hit the “read more” button for the FAQ!

Build your own Litecoin Mining Rig, part 4: Optimization

cgminer with optimized settings

One of my optimized rigs, using the hardware from part 1 of this guide, getting over 1.9 Mh/sec in cgminer while using about 680 watts of power.

This fourth installment of our litecoin mining guide will focus on getting the most out of your hardware—finding the sweet spot between maximum performance and acceptable power usage (and noise/heat generation!).

The tweaks that I outline in this article are applicable whether you’re using Linux or Windows. If you’re using the hardware that was recommended in the first part of this guide (or very similar hardware), you should expect to see a performance increase of 10% or more in your litecoin mining hashrate, compared to the baseline cgminer settings that were given in our Linux and Windows setup guides.

In addition to increasing your mining speed, I’ll also show you how to set up a backup mining pool to automatically failover to in case your primary pool becomes unavailable. There is nothing worse than having your mining rig(s) sit idle because your pool went down!

Click “read more” for our mining performance optimization guide!

Build your own Litecoin Mining Rig, part 3: Windows Setup

Litecoin mining setup guide for WindowsBy now you’ve probably seen our Linux Litecoin mining setup guide (and hopefully the hardware guide that preceded it). Perhaps you’ve decided that Linux just doesn’t seem like your cup of tea. If Windows is more your thing, you’re in luck—this guide is for you.

Let me just reiterate that for most people, Linux is likely the better choice. With Linux, you can use a $5 USB stick instead of a $50 harddrive, and you save yourself the cost of a Windows license as well. The actual mining performance will be the same on either platform, so the cost savings of Linux would seem to make it a no-brainer as long as you’re comfortable with the slightly more complex setup (although our guide makes it simple!).

However, if you have GPUs that aren’t voltage-locked (such as the MSI 7950s that we recommend in our hardware guide), and you plan to take advantage of that feature to undervolt your cards (we’ll show you how), Windows might become the better long-term option for you, depending on how much electricity costs in your area (edit 10/2013: easy undervolting in linux is now possible, too).

So with that in mind, if Windows sounds like it’s the right choice for you, read on for our setup guide!

Build your own Litecoin Mining Rig, part 2: Linux Setup

Linux Litecoin Mining Setup Guide
In the second installment of our DIY litecoin mining guide, we’ll look at how to install and configure Linux to properly mine with your GPUs at optimal settings. Don’t be dissuaded if you’ve never used Linux before—our step-by-step guide makes it easy.

Linux has a few advantages over Windows, including the ability to install to a USB stick (which means you don’t need a harddrive), lesser hardware requirements (you can get by just fine with less than 4GB of RAM), and simpler remote administration capabilities. Best of all, Linux is free! However, be aware that if you’d like to undervolt your GPUs to save power, Windows might be a better choice for you (update 10/2013: no longer true!).

If you missed the hardware portion of our guide, make sure to check it out first. Otherwise, read on.

Build your own Litecoin Mining Rig, part 1: Hardware

Litecoin mining rig in plastic crates

One of my finished mining rigs. Using plastic crates instead of a standard PC case helps improve airflow and cooling.

So you’re interested in mining cryptocurrency, but you’re not sure where to start? No problem, this guide is all you need to set up your own headless litecoin mining rig—even if you have absolutely no experience with this sort of thing.

First, let’s get the obvious question out of the way: why litecoins? After all, bitcoins are worth more, right? The simple answer is that at the time of this writing, litecoins are currently the most profitable cryptocurrency to mine when you take into account how much each coin is worth, and the time required to mine one. Rest assured that if the situation changes, and another cryptocurrency suddenly surpasses litecoin as the best mining option, the rig outlined in the guide should have no problem switching over to a new coin.

This guide will be broken into several parts, each focusing on a different aspect of building your first mining rig. First, let’s take a look at what you’ll need in terms of hardware to put a respectable miner together.