Build A Dual-Core PC Without Busting Your Budget

In financial terms, because dual-core chips are the latest technology, there's less of a price differential between an off-the-shelf box and a system you can piece together yourself than is the case for low-end processors. As a consumer, rather than being forced to choose from a Chinese menu of canned configurations, you can spend your money on pure performance.

Building your own hot computer is also a valuable learning experience, one you'd do well to consider taking advantage of before PCs become like today's cars, with few user-serviceable parts inside.

In this article, we'll build a system around a dual-core Athlon X2 processor from AMD. In a future article, we'll construct a separate box using a dual-core Pentium D from Intel.

In terms of price, we're taking a two-pronged approach. We're building a high-end PC appropriate for multimedia or gaming, which will cost about $1,400. However, if you choose a slightly slower dual-core processor instead, you can bring the project in for less than $1,000. My philosophy in approaching the build is to go for fun and pretty much good enough, as opposed to doing an exhaustive analysis to obtain the absolute best components for the price for every aspect of the PC.

In the interest of full disclosure, AMD provided both the processor and the motherboard for our project. The rest of the stuff we paid for ourselves.

Processor: Athlon X2

The Athlon 64 X2 5000+ has two cores and runs at a clock speed of 2.6 GHz.
Click image to enlarge.

The heart of any dual-core PC is the processor; it can also be a budget buster unless you choose your CPU carefully. Currently, the ne plus ultra of dual-core processors are Intel's 3.2-GHz Pentium Extreme Edition, which sells at a street price of around $1,050, and AMD's 2.6-GHz Athlon 64 X2 5000+, which retails for about $745.

While each chip has its advantages, we're going with the AMD for two reasons. For one, it's $300 cheaper. The Athlon has also been acclaimed as a solid performer.

On the Intel front, the performance buzz is focused less on its existing Extreme and 9XX line than on its upcoming Conroe family. Early benchmarks of the Conroe Core 2 processors due from Intel in July have been impressive. We'll wait for those to use in our next project.

Perhaps the most important reason to wait for Conroe is that it will constitute Intel's first true, from-the-ground-up dual-core architecture. Intel's current 9XX dual-core line, like its 8XX predecessors, use a dual-die configuration. This means the two cores exist on the chip as separate slices of silicon. Because they're discrete, they must communicate over a front-side bus, albeit a fast, 800-MHz FSB. In contrast, Conroe will have its two cores located on the same silicon die, enabling faster interprocessor communication and a shared L2 cache.

For our AMD build, there is a budget option, if you want to build a hot dual-core box that nevertheless costs you less than $1,000. The 2.0-GHz Athlon 64 X2 3800+ uses the same AM2 socket as the 5000+ -- so it'll fit in the motherboard we've chosen -- but at $325, it's less than half the cost of the Athlon 64 X2 5000+.

Motherboard: Asus M2N32

The Asus M2N32-SLI motherboard.
Click image to enlarge.

While the processor is the key visible performance element of the PC, the motherboard is no less important. Unfortunately, the motherboard is like the crate engine of the computer world, a component that's so critical it's paradoxically an afterthought on many builds.

Compared to the mobo, choosing a processor is easy. The CPU universe is relatively constrained, with selections limited to vendor -- AMD or Intel -- number of cores, and choice of clock speed and cache size. In contrast, there are thousands of motherboards to choose from. Asus, Abit, AOpen, Intel, MSI, Mach, Mercury, Gigabyte, and Biostar are among the vendors offering Socket 775 mobos.

The first thing you need to do is to ensure your motherboard accepts the correct socket for your processor. Our Athlon 5000+ uses AMD's new AM2 socket, with which the company debuted support for DDR2 memory.

Once that's out of the way, most mobo selections are made on price. That's not a great idea. That's because, more than for any other component, the selection of the motherboard can present a minefield to the novice builder. The hidden danger lurks in the one component you probably never give a second thought -- the capacitor, which zaps voltage spikes and keeps noise out of the circuitry. (In technical terms, it functions as a bypass cap, whose purpose is to shunt AC to ground.)

In good designs, a few dozen capacitors are sprinkled throughout the board; often, they're located around the perimeter because that's where the power runs lie. Poor-quality boards have few capacitors, which themselves are often of poor quality, subject to leakage or burn-out.

Many of the worst mobos are no-name brands. Therefore, the best advice is to stick to a well-known maker of high-quality motherboards, or to ensure that the vendor you buy from has a good return policy. (Though veteran builders know that even policies that sound good may be meaningless, since once you've got the board in hand, most resellers refer you to the manufacturer's warranty service if anything goes wrong.)

Our motherboard is the Asus M2N32-SLI Deluxe motherboard (we got the deluxe, not the wireless, edition). It's widely available for $215 to $245, depending on where you buy. Asustek, which makes the board, has improved steadily over the years and makes a good product. I'm a big fan of Intel motherboards, but, of course, Intel doesn't make boards for AMD processors.

Graphics Card: Budget All The Way

In this build, my biggest challenge was picking a graphics card. That's because I'd previously spared myself the expensive of a separate SKU by opting for motherboards equipped with integrated graphics. That's an approach looked down on by gamers, but since my main PC apps are Web surfing, e-mail, and word processing, I really have little need for heavy-hitting 3D graphics.

However, with Windows Vista on the horizon, you will need good graphics performance if you want to run the Aero user interface that's the highlight of the upcoming OS. The GUI features see-through "glass-like" 3D icons and all sorts of funky imagery. (See a Microsoft video demo, here.)

This means you'll need a separate card, which plugs into one of the motherboard's PCI Express (PCIe) slots. And make sure it can handle Microsoft's new graphics requirements, which include support for monitor resolutions of 1.3 million to 2.3 million pixels.

Despite such seemingly intimidating requirements, unless you're a hard-core gamer, a budget graphics card should suffice. (As one Slashdot poster put it, "Gamers have been successfully brainwashed that they need a $500 video card to play a modern game, while the low range has been excellent for the past three [to] four years.")

The desire for performance will always butt up against budgetary considerations. Though I'm not a gamer, I covet slightly better graphics power for the online videos I increasingly watch. That's why I went with a budget card.

Specifically, I chose the Leadtek GeForce 6200. It's inexpensive -- I paid $45 -- and has received a couple of good reviews. The one false step I made in my purchasing decision was not going for more video memory. To be Vista-ready, 256 MB is the surest way to go. I'm kicking myself because I could have gotten at least 128 MB of video memory, instead of 64 MB, for an additional $5 if only I'd have read the video card's online description more carefully. (It read "supporting 256 MB"; the fact that the board was fitted with only 64 MB was hidden in the detailed specs. My bad.)

Hard Drive: Don't Skimp On Storage

When it comes to mass storage, I shop mostly on price. Sure, I might be leaving some performance on the table, but I don't have the budget for a 10,000 rpm, 300-GB Ultra320 SCSI drive that sells for $700+.

Drives are pretty cheap nowadays. Still, I was pleased with myself for finding a 200-GB Hitachi hard drive for only $88. It's got a relatively old fashioned ATA-100 interface. Many builders will prefer to go for a newer SATA drive. On this one, I'm agnostic. After capacity, my main criterion is reliability, and I've had good experience with Hitachi drives.

Ultimately, the choice of hard drive could become moot as flash memory begins to take over as the main storage device. However, that's likely to happen on laptops well before it becomes a reality on higher-capacity desktop PCs.

Memory: A Gigabyte Of DDR2

With RAM, most any brand will do, but make sure you get the correct type. Old-style 100-MHz and 133-MHz SRAM, found in many PCs still in use, has given way to DDR memory. Higher-end equipment, like our motherboard, uses the still newer DDR2 memory. Even within DDR2, there are multiple speed grades. Check your motherboard's spec to see which of the PC4200, 5400, 6400, or 8000 speeds is the highest it supports. (You can buy faster memory than your board is spec'd for, but it won't run at its full speed.)

Memory is cheaper than it was a decade ago, but its cost hasn't come down as much as that of other components. It still rankles to part with nearly $200 for 2 GB of RAM, which is a safe capacity to ensure the machine will be truly Vista ready. That's why I wimped out and paid $80 for 1 GB of PC4200 DD2 RAM from Buffalo Technology.

Operating System: It's Still Windows

While Linux makes sense from a price and functionality standpoint, one can't get away from the "mainstreamness" of Windows. If Windows XP Home were only available for its list price of $200 for the full version, I'd have gone with Linux. But the OEM version of Windows XP Home is widely available for around $89. You can qualify to purchase this version as long as you're buying parts to build a PC from scratch.

The psychological lesson I took from my bout with the Windows versus Linux decision is that sub-$100 pricing is the tipping point that can sway the decision. We don't yet know what Microsoft plans on charging for the six Windows Vista SKUs it's releasing. If Vista is really cool, I'd probably pay $85 to upgrade. I might even pay $110. But $250 would send me permanently over to Linux.

Case: Basic Black

Inside view of the completed PC. Note the wires neatly tied up out of the way.
Click image to enlarge.

If you want to funk up the look of your computer, there are several sites that'll cater to your case-mod needs. If acrylic, aqua blue, aluminum, or even liquid-cooled cases are your thing, they're available from Crazy PC, Frozen CPU, and Xoxide, to name just a few.

Moi, I'm happy with a basic black and silver unit, as long as it comes with a power supply, eliminating the need to shop for that separately. That's what I got with a $30 ATX mid-tower case made by Diablo Tek. The company is a somewhat mysterious Taiwanese firm that's everywhere and nowhere; its cases are ubiquitous, but Diablo Tek itself doesn't seem to have a working Web site.

DVD Burner: Bye, Bye CD Drive

With DVD burners selling for what a decent CD-ROM drive did several years ago, there's no reason not to outfit your PC for video. Indeed, these things are so cheap now that most manufacturers make little, if any, profit on them.

I opted for a $40 AOpen model on the theory that if it breaks, I can simply replace it. If you shop carefully, you can get your burner bundled with a free copy of a DVD-burning program, such as Nero.

One thing I'll be interested in testing is whether the dual-core PC offers any noticeable speed-up in the time it takes to burn a DVD or audio CD.

The Build: Mechanical Morass

Most build-a-PC articles don't focus on the construction process, going straight from the bill of materials to the benchmarks with nary a word about problems encountered along with way. Whether that's because you're not really building something so much as connecting up a bunch of boards and wires -- in the manner of the Heathkits of yesteryear -- or because there's little recourse if the completed box doesn't work, I can't say. My experience was consistent with that of past builds. As I expected, most of the difficulties were mechanical in nature, having to do with the fit and finish of the case and the seating of boards. Here, it helps to keep handy a junk pile of extra machine screws accumulated from your past computer projects. If there's one item I'd put more money into next time, it'd be the case. While I liked the look of it, the $30 unit I used was just close enough to spec to be annoying, challenging me to force every component that extra millimeter left or right, the better to get the screw in. Wedging the rear-connector faceplate -- through which the motherboard's audio, networking, USB, mouse and keyboard jacks pass -- into the case took me on a major tangent into aluminum crimping and bending. Not that I'm one to read directions, but the documentation that came with the Asus motherboard gets a C-minus. Everything was in there, but nothing was easily accessible. The diagrams looked like they were designed to be smuggled out of the country rather than to help one distinguish among 20 connectors that look alike.

Heart Of The PC

The PC Probe II utility monitors CPU temperature, voltages, and fan speed.
Click image to enlarge.

Better to take the approach Intel does with its boards: include large, fold out "idiot guides" that graphically illustrate the 20 sequential steps you need to take to connect up your board. On the plus side, the Asus M2N32-SLI was a bit bigger than the average motherboard (the better to hold its massive heat sink), which made navigating the manual's desultory diagrams a bit easier. The acid test of a PC construction project is the initial boot-up. To save a few bucks on the build, I hooked the completed box up to a monitor, keyboard, and mouse I had lying around. After an initial blank screen due to a monitor connector that had fallen onto the floor, I'm happy to report the Athlon box performed like a champ.

The first order of business was getting into the BIOS setup to change the boot order and put the CD-ROM/DVD drive at the head of the list. This was necessary so that the system would recognize the Windows XP disk and install the operating system.

Forty minutes later, I was set to go. The next difficulty I encountered was I couldn't connect to the Internet, despite an icon that assured me I was the proud user of a 400-Mbps link. Turns out the high-performance Asus mobo's LAN ports support Gigabit connections, which don't work and play well with my low-end Belkin router. An old 100-Mbps networking card, which I retrieved from my junk pile and plugged into a PCI slot on the Asus, got me online.

Windows XP clearly recognized my Athlon 64 x2 5000+ as a dual-core, 2.612-GHz processor. I can't quote PCMark or SYSMark benchmarks because I'm not a corporate subscriber to those tools. The best anecdotal -- albeit non-technical -- testimonial I can quote is from my teenaged daughter, who happened by and remarked, "Wow, Dad, that's fast."

On the downside, the unit runs hotter than I had hoped. That must be something the manufacturers are aware of because AMD's Cool 'n Quiet driver is included to rein in processor power consumption.

In addition, Asus included PC Probe II, a utility that posts on the screen a dashboard monitoring the CPU temperature, voltages, and fan speed. This allows you to keep a constant eye on whether you're about to red-zone. While there's no need to get extreme and water cool the CPU, I am planning to add an extra case fan.