How To: Build a 'Double-Powered' Gaming PC


Good things come in pairs. To create the ultimate high-power system, throw in two of everything


The key to building a powerful and speedy PC for gamers and other computing enthusiasts is simple: Throw in two of everything!

Take a look at what the competition is doing. First-tier manufacturers of CPUs, graphics processors and system chipsets have recently discovered that a fast, easy and cost-saving way to boost a PC's performance is simply to double-up on whatever the system needs for power and speed. The process began several years ago, when motherboard chipset designers and RAM companies realized they could improve overall system performance by including two memory controllers instead of just one. Thus was born dual-channel memory.

Later came "RAID striping," or enabling two disks to be ganged together to form one large virtual disk. This became popular as motherboard builders and chipset designers began incorporating RAID directly into their designs, even for low-end systems.

More recently, this trend has gone straight to the silicon. Both Intel and AMD have decided to take a breather from escalating clock speeds and instead focus on packing more computing power into a single chip package. That philosophy gave rise to Intel's Pentium D and Celeron D lines, and AMD's Athlon 64 X2, which are all "dual-core" designs that effectively turn a single-socket computer into a dual-processor machine. (For more information on this subject, see a recent TechBuilder Recipe: Build A Dual-Core System.)

Even the graphics-chip companies have gotten into the act. Nvidia and ATI have both reintroduced a technique not seen since the late 1990s, when the now-defunct firm 3dfx Interactive shipped the Voodoo graphics card, which was SLI, or "scan line interleave" capable. In essence, SLI technique let users gang together two video cards to act as one, leading to faster, more detailed 3D rendering. While 3dfx is no longer with us, SLI did survive. Today Nvidia calls SLI "scalable link interface," but the net result is the same: Put two video cards together to do the work of one, and a video game's frame rates and explosions-per-minute go through the roof.

For this Recipe, I'll take you through the steps on a system build packed with twins that will deliver a powerful punch at the high-end of your consumer desktop line.
Ingredients

  • Asus A8N-SLI Premium motherboard: The heart of our system will be Nvidia's Nforce4-based A8N-SLI motherboard. As the name suggests, it comes with the two PCI Express x16 slots necessary for a modern SLI configuration. In keeping with our theme, this motherboard also boasts two RAID controllers and two Ethernet ports. The extra RAID controller—a Silicon Image chip complements the onboard Nvidia RAID controller—and the second gigabit Ethernet port won't actually make the computer faster, but they do make it markedly more flexible.
  • Thermaltake Tsunami VA3000BWA case: A machine with two of everything needs breathing room. This desktop case provides three integrated fans and plenty of expansion (and airflow) room.

  • Antec TruePower 2.0 TP2-550 EPS12V ATX12V 550W power supply: You read that correctly, a 550-watt power supply, more than many servers need. The power requirements created by "two of everything" are, in a word, ridiculous. Most home PCs are more than comfortable with a 300-watt supply, and many of the new low-profile or "shoebox" PCs do not supply even that much. But by doubling-up and using the latest high-end silicon, we gain performance merely by adding more juice. The motherboard alone needs three power connectors plugged into it, and each graphics card has its own heavy draw. This power supply is on NVIDIA's SLI-approved list and has power connectors to spare, so it can be installed with confidence.

  • Plextor PX-716A/SW DVD burner: This one of the few parts that we only need one of! Two drives would make it easier to use the machine for CD or DVD copying, of course. But either way, this drive boasts a generous 8 MB cache, virtually eliminating any chance of a write failure.

    The PX-716A is a conventional parallel ATA drive. A SATA version is available, but because it's more difficult to boot to DOS or directly off a number of CDs with serial ATA optical drives, I still recommend the parallel version. If you do opt for the SATA version—which, admittedly, would improve airflow inside the case—be sure to supply the two necessary RAID floppy disks to the customer at time of purchase (see step 13 below for more on this).

  • A pair of Western Digital Caviar SE WD2500JD 250GB disks: Striped in tandem on one of the motherboard's RAID controllers, these two drives will provide a half-terabyte of storage.

  • AMD Athlon 64 X2 4400+ Toledo: One of AMD's highest-end offerings, the dual-core 64-bit compatible processor acts as two CPUs, each with independent cache. But it fits in the single Socket 939 mounted on the motherboard.

  • A pair of Transcend 512-MB 184-Pin DDR SDRAM DDR 400 RAM sticks: The A8N-SLI does not support higher-speed DDR2 memory, so go with a solid DDR400 selection. This RAM is on ASUS' approved list for the board. By installing in matched pairs, the Nforce 4 chipset can put its dual memory controllers to optimum use.

  • A pair of Asus EN7800GT video cards: Equipped with an Nvidia GeForce 7800 GT chip and 256 MB of high-speed DDR3 RAM each, these monstrous video cards are the heart of the high-performance visuals this machine can produce.

  • Microsoft Windows XP Professional, Service Pack 2 (SP2): This desktop OS is still the de facto choice for high-end enthusiast computing.

  • Floppy disk drive: Since Windows XP inexplicably cannot read SATA drivers off any media except a floppy disk, you will need to include this drive to ensure that the system can be fully installed and restored while using the SATA RAID.

Now that you've assembled your components, let's start building. Place the components on an anti-static workspace. You'll need only one tool: a small Phillips-head screwdriver.

  1. Install the motherboard in the case. Because the weight of the graphics cards and the Athlon 64 X2 heatsink will be considerable, be sure to use all of the screw mount points on the motherboard to secure it to the backplane of the chassis. Attach all three of the necessary power connectors to the motherboard. Note: There should be one large ATX cluster, one four-pin square connector, and one four-pin Molex connector leading to the board.

  2. Install the RAM. The A channel and B channel are separated by a small gap. Place one DDR module in slot A1 and the other in slot B1.

  3. Install the CPU. Give the Athlon 64 X2 a visual inspection for bent pins—there are several hundred of them, and plenty of opportunities for flaws—before you open the ZIF lever and mate the chip. The Athlon has a notched corner as well as physical keying in the pin array that should prevent incorrect insertion, but double-check before mating the chip. Hold the chip down gently with one finger while sliding the ZIF lever closed with your other hand. Next, apply a small amount of thermal conductive substance to the center of the chip and install the chip cooler, being sure to latch the rotating arm in place. Ensure that the fan is connected to the nearby 3-pin fan power jumper.

  4. Install the optical drive in one of the case's external 5.25-inch drive bays. Configure the jumper for Master mode. Connect the parallel IDE cable to pad PRI_IDE on the motherboard.

  5. Install the floppy drive in an external 3.5-inch drive bay. The floppy controller on the motherboard can be found next to the large power-supply port.

  6. Install the two hard drives in internal 3.5-inch drive bays. Connect them to the first two SATA ports supported by the Nvidia chipset. Note there are eight SATA ports total on this motherboard. The Nvidia ports are the four closest to the edge of the motherboard, and their sockets have a plastic sheath around them.

  7. Remove the blanking plates from the two PCI Express x16 slots and from one of the slots in between. Install the two EN7800GT video cards in the PCI Express x16 slots. Be sure that the plastic retaining clip hooks itself around the front edge of the card connector. Next, connect the video cards to power using the special power cables provided in the box. Note that the top card—the one in the blue socket—will provide the actual display.

  8. Find the SLI bridge from the motherboard kit. It is a small rectangular circuit board with two card-edge sockets. Ease the bridge across the top of the two video cards. It should mate perfectly into the small card edges adorning the top of both video cards. If it doesn't, chances are you are using a bridge from a different motherboard. If that's the case, go back to the box to locate the correct version. Next, to secure the bridge so that it cannot come loose in transit, install the special L-shaped retaining bracket included with the motherboard into one of the card-edge slots between the two EN7800GT boards.

  9. The system is now ready for boot. Connect a DVI monitor to the top EN7800GT card, and power up. Enter the BIOS by hitting the DEL key.

  10. In the BIOS, browse to Advanced Settings/Onboard Devices/NVRAID Configuration. Enable RAID for at least the first two SATA ports.

  11. Still in the BIOS, browse to Advanced Settings/Onboard Devices/SLI Configuration. Ensure EZ-Plug Warning is set to Enabled, and AI-Selector is on Auto. Save the BIOS settings and reboot.

  12. Press F10 during the boot sequence to enter the Nvidia RAID utility. Using the cursor and Tab keys, select a striping array with a 64K block size, and move the two WD2500JD disks listed in the Free Drives to the Array Disks column. Press F7 to commit to your decision. The RAID utility will format the drives for striped array use. Save these settings and again reboot.

  13. Have two blank floppy disks (not CDs) ready for this step. Insert the motherboard-support CD in the optical drive, and boot from it. Select both the Make Nvidia RAID Driver disk and Make Silicon SATA RAID Driver Disk options. To let the system create the driver disks Windows will need in order, insert one floppy in the Nvidia driver, label it, and then set it aside. Then repeat with a second floppy for the Silicon driver. You will need the Nvidia disk in the next step, because we connected the hard drive to the Nvidia RAID controller. The Silicon disk can simply be filed with the materials you will deliver to the customer.

  14. Reboot the system, then insert the Windows XP Professional installation CD. Install the system as normal. When the installer asks for additional drivers, press F6 and insert the Nvidia RAID Driver disk when prompted to load in the correct support software. Then continue with the Windows XP install as normal.

  15. When Windows XP boots for the first time, insert the motherboard support CD, and install the Nforce 4 motherboard drivers. Reboot the system when prompted.

  16. Install the GeForce drivers from the driver CD included in either one of the EN7800GT kits. Reboot the system when prompted.

  17. To fully enable the SLI bridge, open Display Properties by right-clicking the desktop, and then select Properties. Click the Advanced button, then select the GeForce 7800GT tab. In the tree option view, select SLI Multi-GPU, and turn on the checkbox for Enable SLI Multi-GPI. Click OK to commit to the changes. The two GPUs will now coordinate activities across the SLI bridge and attempt to share the graphics-processing load equally, boosting overall video performance.

This build delivers a lot of raw power, and the system requires a lot of juice from the power supply. But when it's finished and running along—your users and customers will love the power of two!

JASON COMPTON is a technology writer who has covered topics ranging from 8-bit entertainment to supercomputing for more than a decade.