LJ Archive

The Ultimate Do-It-Yourself Linux Box

Nicholas Petreley

Issue #148, August 2006

Start with the ultimate AMD64 motherboard and build on it to create a masterpiece of your own.

Some of us just like to do it ourselves. There's something uniquely satisfying about selecting every component in a system. It allows you to balance the exact price/performance trade-off that suits you best. Do-it-yourself is also one of the best ways to ensure that you have a system that won't become obsolete within six months. For example, most AMD64 motherboards support only 4GB of RAM, but our favorite board supports up to 8GB of RAM. We may never upgrade it to the full 8GB, but it's nice to have that room for expansion. You may not get that kind of room for expansion with a pre-made system.

For those with little patience, we'll get right to the bottom line. Our favorite do-it-yourself combo includes the following:

  • Motherboard: ABIT AN8 32X 939

  • Processor: AMD64 4200+ Athlon X2

  • Power supply: Silverstone SST-ST65ZF 650 Watts

  • Memory: two sets of Corsair 1Gx2 TWINX2048-3200PRO modules (four total)

  • Video cards: matched pair of eVGA GF 7900GT 256 (NVIDIA SLI)

  • Case: Silverstone TJ07-S

  • Hard drives: 2x Seagate Barracuda 300GB 7200 RPM 8MB cache SATA 3.0Gb/s

  • DVD R+W: Plextor PX-716AL/SW SATA

  • Monitor: Samsung LCD 204B 20.1"

  • Keyboard: Logitech Cordless Comfort Duo (includes mouse)

  • Mouse: Logitech G7 Laser Cordless mouse

The above list includes the G7 Laser Cordless mouse simply because that is what we ended up using, but we do not include it in our price lists. Your choice of keyboard and mouse are more personal than just about anything else on your system (save, perhaps, your monitor). We like the keyboard in the Logitech Cordless Comfort Duo but not the mouse. So we replaced the mouse with a Logitech G7 Laser Cordless mouse. We don't assume any of you are going to do the same, so we don't make a fuss about keyboards and mice in this do-it-yourself system.

The Do-It-Yourself Goal

Our goal for the do-it-yourself system was to create a high-powered Linux desktop without breaking the bank. Bang for the buck was our motto. We created a powerful system with components that often fell just below the big price breaks, after which you tend to pay a lot more for only minimal performance gains. In addition, we opted for a fan-based enclosure instead of a more expensive (and usually harder to install) liquid-cooling system.

We also include an alternate budget-minded system. Our do-it-yourself budget system is still pricey, but it delivers a lot of power at a considerably lower price than our favorite configuration.

One very important consideration in our choices was, will this work with most Linux distributions “out of the box”? We installed Debian, Ubuntu/Kubuntu, Fedora Core 5, SUSE 10 and Mandriva on our do-it-yourself system. All of these distributions ran without any trouble and without the need for any additional drivers or special driver management. (We did, however, use the proprietary NVIDIA drivers, not out of necessity, but in order to make use of the SLI features of the motherboards.) We also ran Knoppix, MEPIS and Kanotix live CDs without problems.

Motherboard

We chose to configure our do-it-yourself system around the ABIT AN8 32X 939 motherboard and an AMD64 4200+ Athlon X2 (dual-core) processor. We chose the AMD64 4200+ based on price. By the time you read this, AMD will have lowered the prices on its line of dual-core processors, so you can get more CPU bang for the same bucks than we did. We used two sets of matched pairs of Corsair memory modules (1Gx2 TWINX2048-3200PRO) for a total of 4GB in four slots in dual-channel mode.

The motherboard is the foundation of any do-it-yourself system. We looked at three motherboards, all based on socket 939 AMD64: the ABIT AN8 32X, MSI KN8 Diamond Plus and ASUS AN832-SLI Deluxe. All three motherboards sell for around $200 US or less, depending on your source. The price difference is not significant enough to choose one over another. All of these motherboards support socket 939 dual-core AMD64 chips and dual-channel memory. All of the motherboards support two video cards configured in SLI mode. We tested the boards with two eVGA GeForce 7900GT video cards configured for SLI.

You aren't likely to be disappointed with any of these motherboards. The MSI comes with the Creative Sound Blaster Audigy system integrated on the motherboard, so Audigy fans will love the MSI. Both the MSI and ASUS boards include two LAN ports vs. one port on the ABIT. So if you want two LAN connections, the MSI or ASUS could be the board for you.

However, it is easy to add network cards and sound cards to motherboards. Despite the fact that the memory controller for the AMD64 is on the chip itself, not the motherboard, it is not possible to force a motherboard to support RAM differently than intended—at least it is impossible to make a motherboard support 8GB of RAM if it is designed to support 4GB or even just 3GB in practice. That is why we felt the ABIT trumped the other boards in the long run. It takes better advantage of the memory addressing capability of the AMD64 processor than the MSI or ASUS. The ABIT motherboard supports up to 8GB of RAM. The MSI and ASUS boards say they support up to 4GB of RAM, but they seem to be designed with 32-bit Windows XP in mind, and therefore use only up to 3GB of RAM by default, even if you have 4GB installed. The AMD64 version of Linux saw only 3GB of usable RAM on the MSI and ASUS boards. Although it may be possible to make all 4GB visible to Linux on the ASUS and MSI boards by playing with BIOS settings, the ABIT saw all 4GB without any BIOS modifications. (The MSI manual implies that it is not possible to make more than 3GB visible on that motherboard, but we did not attempt to prove or disprove the implication.)

We populated the ABIT with four 1GB RAM modules, for a total of 4GB. If you run 32-bit Linux, you should still be able to use all 4GB of RAM. A properly configured 32-bit Linux kernel will map the RAM such that a portion of it goes to the kernel and the rest goes to user space. Linux splits up the RAM depending on how you have compiled the kernel (or how it is precompiled on your distribution).

All of these boards have one more unexpected memory quirk. When you populate all four RAM slots, the motherboard clocks back the memory. In our case, it clocked back our memory from 400MHz to 333MHz. This happens regardless of the memory size of the modules you use. The motherboards will clock back the RAM based on the fact that you have populated all four slots, not based on the total RAM in the system.

Again, it should be possible on all of these motherboards to adjust the BIOS settings to reset the clock speed back to 400. The BIOS on one board may make it more difficult to do so than on another, but by the time we addressed this issue, we already were sold on the ABIT. We were able to change the clock speed back to 400 on the ABIT board very easily. We simply set the DRAM timing settings to run “By SPD” (by the speed of the modules). This reversed the clocking back of the RAM and set the speed back to 400. We haven't experienced any instability at this speed, so it appears to be quite safe to make this change. Granted, you may not notice a performance improvement with the higher speed. When it comes to RAM, latency settings tend to affect performance more than speed. We did not risk changing the latency settings to something other than the specifications of the memory modules.

At this point, you should ask yourself whether you really need 4GB or more RAM. A total of 4GB could easily be overkill for many, if not most, users. If you think you will be content with less RAM for the life of your system, that gives you more reason to consider the MSI or ASUS boards, because all three boards will handle two 1GB modules (for a total of 2GB) equally well. But if, like us, you're a glutton for RAM, the ABIT is the clear choice, regardless of whether you run a 32-bit or 64-bit Linux system.

Power Supply

Never underestimate the importance of a good power supply for your do-it-yourself system, especially if you intend to use two video cards configured in SLI mode. You can experience all kinds of bizarre symptoms of instability if you underpower your system with an inadequate power supply. Don't go for anything less than a 500-Watt power supply if you intend to use two video cards in SLI mode. Go even higher if you intend to add other PCI cards to your system. And, when you shop for power supplies, be careful to look for efficiency ratings. Some power supplies boast good peak output, but the sustained output can still be inadequate.

There's almost no point in choosing a power supply based on its rated mean time between failures (MTBF), that is, how long it should last. We suspect these figures reflect how long the power supply lasts assuming the fan never fails. Unfortunately, power supply fans fail all the time. The power supply overheats, and kablooey, so much for the mean time between failure rating. Your mileage may vary, but we've had the best luck with Enermax power supplies and their fans.

You will need a power supply with a 24-pin power connector to the motherboard for any of the motherboards we tested. You also will need a power supply with connectors for two video cards, so that you can use these motherboards in SLI mode. We chose the Enermax ELT500AWT 500-Watt power supply for our system. It sells for about $100 US, depending on your source. We also used a Silverstone SST-ST65ZF 650-Watt power supply for a similarly configured system. It sells for about $170 US, depending on your source. We've had these power supplies only for a few weeks at the time of this writing, but they both work well so far—knock on wood.

Case

We pulled out all the stops when it came to a case for our Ultimate Do-It-Yourself System. We chose the Silverstone TJ07-S case, which sells for about $365 US, depending on your source. This is quite expensive for a case, but it is worth the investment. First, the thing is huge. It's larger than any tower case we've ever tried. This gives you tons of room to work when you insert cards and cable the system. On the other hand, if you're looking for a case you can place on top of the desk instead of beside it, this is definitely not the case for you.

The hard drives are tucked away in two separate removable compartments, and each compartment is cooled with its own separate 120mm fan. It has two more 120mm fans at the top of the case, and two rear 92mm intake fans. The case is remarkably quiet, considering it has six fans, not including the CPU fan, power supply fans and so forth. All this ventilation keeps everything very cool without having to invest the time and effort in creating a liquid-cooled system.

The case has a flip-down front accessory panel with connectors for audio, USB and FireWire. The panel is flush with the front of the case, so you simply press on the bottom of the panel to open it. Some people might be annoyed that there's no spring loading, no button and no catch for the panel, either in its open or closed state. We have no complaints with it though.

The only way to press the reset switch is to use a wire tool, which you insert into a small hole in the front of the case. Some people will hate this feature, others will appreciate how it protects you from accidentally resetting your system.

You can certainly find adequate cases for far less money, and some of them may even place things like the accessory jacks in more convenient locations. But, we found this to be a superb case primarily because of how easy it is to work inside it (thanks to its gigantic size) and superior ventilation without having to use liquid cooling.

If you're going to go the budget route, there are so many decent cases from which to choose, we're hard pressed to recommend one over another. Each has its advantages and disadvantages. We chose the Thermaltake Tsunami VA3000BWA, which sells for just over $100 US at most outlets. It's not as high class as the Silverstone, and we found it frustrating to get the DVD drive installed, but it's a fair case for the price. It has a flip-up top accessory panel. People who leave things on top of their computer case will find this inconvenient, but the same must be said of the Silverstone case, as it has top-mounted fans you can block by leaving manuals or other paraphernalia on top of the computer.

Video Cards

Yes, you can use two NVIDIA cards in SLI mode on Linux—if you don't mind running the proprietary NVIDIA driver, which taints the Linux kernel. We chose a pair of eVGA GeForce 7900GT cards with 256MB of RAM. These cards are a great compromise between price and performance. The combination of cards totals at about $500 US, which is less than the price of a single NVIDIA 7900 GTX card (about $570 US). eVGA sells basically the same cards with different clock speeds at different prices. For example, budget-minded folks can get a single eVGA GeForce 7900GT Signature 256MB (same basic model as the ones we used in SLI mode) with higher clock speeds for about $360 US.

You obviously have more choices than eVGA when it comes to video card manufacturers. We chose eVGA for our examples simply because the company produces a large selection of prices and configurations of NVIDIA cards, which made it easy to pick cards to fit varying budgets. We've had good success with other brands as well.

If you opt to use the NVIDIA proprietary drivers, you need to add the following line to your xorg.conf file:

Option	"SLI"	"Auto"

We also recommend that you dig through the NVIDIA HOWTO to learn how to specify whether you're using a digital or analog connector. Some monitors like to guess which interface you're using for five seconds or so, which can cause annoying delays when you start your desktop.

Drives

You've got a wide range of drives to choose from, and good SATA drives are amazingly inexpensive. We chose two Seagate Barracuda 300GB 7200 RPM drives with 8MB Cache. These drives are SATA 3.0Gb/s drives, so they're fast, and all three motherboards can handle these types of drives. We chose two identical drives for RAID 0 configuration, which produces even faster disk access (though without any fault tolerance). You can pick just one of these if you're on a budget. They go for about $100 US each. If you're not a fan of Seagate for any reason, you can get other brands of drives that work just as well for about the same price.

Plextor offers a SATA DVD R+W drive, the PX-716AL/SW for about $150 US. This drive has the following write speeds: DVD+R at 16x, DVD+RW at 8x, DVD-R at 16x, DVD-RW at 4x, CD-R at 48x, CD-RW at 24x, DVD+R DL at 6x and DVD-R DL at 6x. It offers read speeds at 16x DVD-ROM and 48x CD-ROM. Be careful when selecting a SATA-based DVD/CD drive, however. You can run into Linux installation problems if you choose a Linux distribution with a kernel configured such that it doesn't recognize a SATA DVD/CD drive properly.

We chose a Plextor PX-750A ATAPI drive for our budget combination, because it costs only about $60 US. You can find cheaper drives, but the less you pay, the noisier and more unreliable they tend to be.

Accessories

Of course, you will need, at the very least, a monitor, keyboard and mouse to have a complete system. We don't make much of a favorite monitor, keyboard or mouse because your favorites will depend a great deal on your personal tastes. Some people like wide monitors; others don't. Some people like wireless keyboards; others don't. Some people like ergonomic design; others don't.

Our summary sample configurations do include a monitor, keyboard and mouse. We did so only to give you an idea of the total price you can expect if you are going to put together a complete system. Your total price probably won't change much if you choose a different keyboard or mouse, but monitor prices vary greatly depending on what kind of monitor you want. So, take our prices with a grain of salt. If you opt for a big, wide-screen monitor, you're obviously going to pay more.

We chose for our example a Samsung 204B, because it has a fairly large screen (20"), good resolution (1600x1200), good contrast ratio (800:1) and an unusually fast response time (only 5ms). It's a great monitor for work and gaming, at a good price—about $400 US.

Extremely budget-minded people can go for something like the Acer AL1515, which is smaller (15"), lower resolution (1024x768) and much slower (16ms). This monitor can be good for work but terrible for gaming. But the price is much lower at about $150 US.

As for keyboard and mouse, we chose two Logitech combinations, the Wireless Comfort Duo (about $75 US) and the wired Internet Pro (about $18 US). You have a lot of wiggle room here. You can get better keyboards and mice without having to spend a whole lot more money, but the Comfort Duo should be enough for most users. We happened to replace the mouse that comes with the Comfort Duo with a Logitech G7 Laser Cordless, but you may find this mouse to be a royal pain, because it requires you to swap batteries as much as twice daily. Fortunately, it comes with two lithium ion batteries, one of which stays in a charger while you use the other. But because this is an unlikely choice for many people, we stuck with the Cordless Duo as the standard choice for the preferred system.

Playing with Prices

We put together two systems, a great system and a more budget-minded system. If you have money to burn, you easily could pump up the great system into an ultimate system. Trick it out with the two best NVIDIA cards on the market in SLI mode. Add a liquid-cooled system that you connect to everything in the box that generates heat. Go for the top-of-the-line AMD64 processor instead of the 4200+. You'll pay a lot more, but you'll get what you pay for. The AMD Athlon 64 FX60 Toledo runs for just under $1,000 US.

The second combo uses a less-expensive case, a single video card and less memory in order to save cash. You can cut other corners as well, but we chose those components that were at a price threshold where a better component would cost significantly more money. For example, at the time of this writing, the difference between an AMD64 4000+ and an AMD64 4200+ is about $30 US, but the price difference jumps to $100 US between the 4200+ and the 4400+. As mentioned earlier, AMD is likely to have restructured all these prices by the time you read this, so the threshold where the price jumps probably will be different. Choose accordingly.

The same tends to hold true for video cards. There's a point at which the price increase doesn't get you much extra performance, so you have to think hard in order to decide whether you want to spend the extra cash for the edge. At the time of this writing, the NVIDIA 7900GT series is affordable and fast. If you really need a budget card, the eVGA GeForce 6600GT 256MB PCI Express x16 goes for about $150 US, and although it doesn't compete well with the 7900 series, it's no slouch.

Perhaps no category includes a wider variety of prices than monitors. We didn't explore the vast range in our do-it-yourself kit, simply because a choice of monitor can be intensely personal. We can't tell you which one you'll like best, but we can tell you that the price difference between a monitor you like and one you love can be as much as $1,000 US or more. We're very happy with the Samsung 204B. You might need more, or you might be happy with less.

Nicholas Petreley is Editor in Chief of Linux Journal and a former programmer, teacher, analyst and consultant who has been working with and writing about Linux for more than ten years.

LJ Archive