Whether you're an experienced hand or a technophobic novice, chances are good that your last PC upgrade didn't exactly follow the industry's best practices. Many newbs flub upgrades through inexperience, but it's just as common to see a hardcore system builder throw caution to the wind while swapping out a CPU, snapping in some RAM, or swapping out a hard drive or graphics card. Whichever camp you fall into, cutting corners as you work on your computer puts it at risk of sustaining damage to sensitive components. In the worst case, you might even destroy the entire machine.
The most common error--and this goes for every type of component upgrade--consists of failing to use static protection. Novices typically don't even realize that static electricity in their body can discharge into a PC's components with just a light touch, potentially damaging sensitive circuitry.
Old hats, on the other hand, have the opposite problem: Years of handling hard drives, memory modules, graphics cards, and CPUs desensitizes us to the very real hazard posed by static electricity, leaving us vulnerable to a problem we know perfectly well how to avoid. So come on, folks. Wear an antistatic bracelet whenever you work on your components.
RAM Upgrades
Memory manufacturers produce RAM with various pin configurations, data rates, and bus speeds. If your laptop calls for 667MHz PC2-5300 modules, but the store has only 1333MHz PC3-10600 for sale, resist the temptation to try the flavor that's available. It won't work, you could damage your PC trying it, and the store probably won't give you a full refund for the opened modules.
The biggest RAM upgrade mistake that experienced users make is to neglect to check the capacity limits of their machine. Some systems--especially netbooks and ultralights (and a lot of Macs)--can accept only a certain amount of RAM. So despite the fact that your local tech store sells 4GB modules that fit in your machine, you could pack them home only to find that your two-year-old laptop takes only 2GB modules. The advice here is simple: Check the manufacturer's documentation before you buy.
Processor Upgrades
Assuming that you've bought the right CPU upgrade for your machine, you still have to avoid three incredibly common mistakes that plague processor upgrades: pin displacement, poor thermal paste application, and improper heat sink installation.
Every PC CPU has lots of little pins that seat them in their motherboard socket to form the vital connections through which the computer's data flows. If one of these pins bends or breaks, you're hosed. So whenever you handle a CPU, take care to avoid touching the pins against anything--your fingers, a countertop, the edge of the case, other system components, anything. Also, don't force the CPU into its socket. If it doesn't fall right into place, something is off--and increasing your pressure on the processor is bound to bend a pin. Instead, lift up the CPU, check that the pins are straight and the socket is wide open, and try again.
In the event that your CPU does have a bent pin, proceed with straightening it out very cautiously. Use a nonconductive material, such as a piece of plastic to gently nudge the pin back into position.
Finally, avoid the mistake of using an inadequate or ill-fitting heat sink with your CPU. If your new CPU is substantially faster than your old one, it probably creates more heat, too. So unless you're already using a high-performance heat sink, consider treating heat-sink replacement as part of the upgrade process. You don't have to go all out with an expensive, complicated liquid-cooling system, but if you're spending $300 on a new CPU, spending $30 to $50 on a high-quality heat sink to protect that investment (and the rest of your PC) makes sense.
Hard Drive Upgrades
Next to RAM, a hard drive is one of the easiest PC components to upgrade. Often, the most difficult part of the process is reaching all of the screws with your screwdriver. That's because many system cases open only on one side, or contain framing components that block access to the drive cage. Resist the temptation to take the easy route of screwing the drive in on only the more accessible side. An unevenly mounted hard drive is likely to wobble slightly in its bay, causing undesirable vibrations that can make your PC noisier than it should be and potentially shorten the drive's life.
Nearly all PC chassis are designed to give you access to both sides of the drive cage. In most instances, the cage itself is removable, so you can snap it out, screw your drive in properly, and then snap the cage back into place. Take the time to do this, and you'll probably reap the rewards of a quieter PC and greater longevity from your drive.
Another common mistake--even among experienced PC builders--is to use the wrong type of screws to mount your hard drive. This error usually isn't disastrous, because the difference in diameter between case screws and hard-drive screws is subtle. But 6-32 case screws are slightly thicker and have a wider thread spacing than M3 hard-drive screws, so using the wrong screw will mangle the screw holes on the drive, which may cause problems later if you ever need to remove and reinstall the drive.
Don't Ignore the Power Supply
If you've made a few upgrades to your system, take a moment to evaluate whether your current power supply is up to the workload you're giving it. Asus has a pretty good power supply wattage calculator to help you with this assessment. You may very well discover that you've been expecting a 650-watt power supply to run a system that can draw more than 800 watts under peak load. Upgrading to a more appropriate power supply can make your system faster and with greater stability.
Routing Cables Neatly
I know how it is: Maybe you're busy, or you don't care about the aesthetics of your system's components, and you just want to finish the upgrade so you can boot the thing and play some games. But it's a mistake to leave your PC's internal cables hanging like an impenetrable cobweb in the middle of your machine.
If you look inside a really sweet machine from a performance builder like Velocity Micro or Maingear, you'll find cables virtually concealed from view, routed behind the walls of the chassis, under the motherboard, and along the corners of the case, held in place by itty bitty zip ties trimmed neatly at the neck.
You don't have to be as fastidious as the pros to give your machine better airflow and a slick, orderly appearance. Just buy a small bag of zip ties and use them to cluster cables together into vaguely coherent pipelines, leaving as much open space as possible in the center of the case. Then take a small wire cutter and snip off the ends of the zip ties.