You can't even begin to call yourself a geek until you've built your own custom computer rig. The price of computer components are at an all time low and building one has never been easier. For just a little bit more than a next generation console you can have a powerful PC that plays current games and so much more.
I've built and upgraded a lot of systems over the past 10 years and I'll let you know about every secret I've learned. I'll walk you through building a nice gaming rig that's stable, fun, and cheap to build, and performs better than most pre-built systems that cost twice as much. If your looking for ideas I try to keep an updated Newegg wishlist that features a $500ish PC (minus monitor and software) that should rock current generation games with no problems. If you got money burning a hole in your pocket you can try a beefer build.
Before we get started, we'll need something to put our components in. A decade ago there weren't many choices for cases but today there are thousands to choose from. The most common specification of case is the mid-tower ATX spec. If you want to build a smaller, more portable system than a micro-ATX or even a mini-ITX case might be for you. Some OEM cases (Dell, HP, etc.) conform to the ATX standard but many do not, so be sure to double check if you want to use the case from an older PC.
When selecting a case be careful about the low budget (less than $40) cases, they are usually made of very thin metal and have little or no support structure. I once ordered a $40ish case and was immediately sorry. It wobbled like Jello and nothing fit easily or correctly. It really turned into an assembly nightmare.
To keep your system's weight low, picking an aluminum case is a good idea. To keep it quiet and cool choose one that uses 120mm fans instead of the smaller 80mm. A few other nice features to look for are tool-less design, fan filters, drive rails with support for 2.5" (SSD) drives, outward facing harddrive bays, motherboard tray, and thumb screws.
After you have your case picked out we'll need something to power your new rig with. Today's gaming PCs typically require a 350-550W PSU. If you're going 8-core, SLI, and RAID than you might require something in the 650-750W range. Again, you usually get what you pay for when it comes to PSUs. The more expensive ones use better cooling techniques and will typically run quieter and last longer. Look for a power supply that meets the ATX v2.3 or better specification.
A PSU must provide many different voltages, called rails, and the wattage rating for a PSU is all of the rail's wattages added together. This is why you must be careful not to buy a PSU based purely on its maximum wattage. Today's PCs often get 80-90% of their power from the 12V rail, however, some PSU manufacturers cheat by allocating an unnecessarily large amount of wattage in the lower voltages so they can claim a 700W PSU that has less power on the 12V rail than some other 400W PSUs. Some of the really high end graphic cards require a huge amount of power from the 12V rail. When selecting a PSU you must be sure to buy one that will supply enough power to the card and still have enough left for the rest of the system. As a somewhat annoying safety (and cost saving) feature, many larger PSUs have multiple +12V rails that will require you to manually balance the load on each rail.
Now you need to pick out a CPU. CPU cores have started to reach a physical limitation in speed. So the next step is parallelization (running multiple algorithms at the same time). This is why dual or quad core processors are now common. However, many games and programs still aren't designed to use multiple processors so they will only use one core while the other cores remain idle. This deficency means that at the moment speed is king and two faster cores are better than four slower ones.
The two kings of processors today are AMD and Intel. As to which one to choose, that's up to you. I've used both in my systems over the years and they both make excellent processors. I always choose by comparing price vs performance. I set a price range, usually between $100-$150, and find the fastest processor I can get for that price. You can get the prices for CPUs from your favorite shopping site and a good set of benchmark results can be found at Tom's Hardware. A guy by the name of Paul Tarjan has also made a nice little web scraper that shows you benchmark/price ratios.
Both AMD and Intel have begun to integrate graphics processing units (GPUs) into their processors and sometimes call them APUs. They can provide decent 2D/3D acceleration but even the best ones don't come close to a dedicated video card. Still, if you're only a casual gamer they work well and provide excellent value.
Now that you have your CPU picked out you need a motherboard to match it. The 'central nervous system' of your PC -- the motherboard connects everything together and makes sure they play nice. Today's motherboards are loaded with extra features like sound, ethernet, USB, RAID, and even sometimes wireless.
Motherboards are designed around a chipset duo, commonly called the northbridge and the southbridge. The chipsets determine what CPU, memory and other features your motherboard will support. Intel and AMD both make their own chipsets for their own platforms and nVidia makes pretty good chipsets for both platforms. New chipsets are always being released to keep up with the latest features so be sure to buy a recent one. If you're looking to run two video cards in SLI or CrossFire mode you'll need to match the appropriate chipset with the appropriate dual-card technology.
Some features to look for in new motherboards are a 16x PCI-e v2.0 slot (or more if you want SLI), dual channel memory support, lots of USB 2.0 ports, gigabit ethernet, and SATA III with RAID support.
Besides your hard drive, RAM is one of the biggest bottlenecks in a modern PC system. Always spend the extra few dollars to get the fastest speed your motherboard and CPU can handle. Most PCs today have switched to the DDR3 memory standard. Purchase at least DDR3-1600 (PC3 12800) with DDR3-2133 (PC3 17000) being highly recommended. In addition to speed RAM is also valued by its latency. You will often see numbers like 8-8-8-24 in the spec which indicate its latency. The lower the numbers the better with the first two numbers being the most important.
How much RAM do you need? Well, as the old saying goes, you can never have too much. Most modern games on Windows 7/8/8.1 won't work well with less than 4GB. If you feel that 8GB won't break the bank then I highly recommend it. [Note that if you don't run a 64-bit OS you will not be able to access more than about 3.2GB.]
When purchasing RAM it is always best to buy RAM in matching pairs. Most motherboards support dual-channel memory. This allows it to access two sticks of memory at the same time, thus doubling your memory speed. Even if your motherboard doesn't have that feature it's still often cheaper to buy your RAM in matching pairs. A few Intel motherboards now support triple channel memory for even higher performance.
Video Card (GPU)
Todays video cards are pretty amazing and often rival or exceed the main CPU in raw processing power. The two top video chip makers are ATI (now AMD) and nVIDIA. Again, just like the CPU, compare price vs performance and read lots of reviews. Make sure you find benchmarks of games that you want to play and see how the cards do. Modern video cards are built for the PCI-e v3.0 bus and should have at least 2GB of RAM. For the best experience get one that supports at least DirectX 11.1.
Most mid-range and higher video cards support parallelization, also called SLI or CrossFire, where you can use two cards to help divide processing. From my experience it's often better to just spend the extra money and get a faster card but if your already at the top then it's the only way to go faster.
The slowest component and biggest bottleneck in current PCs is the hard drive. It doesn't matter how fast the rest of your system is, if it can't get the data off the HD fast enough it's going to be waiting around most of the time. Today's common standard is SATA 6Gb/s, sometimes also (incorrectly) called SATA III. They usually come in 7,200 or 10,000 RPM spin speeds and feature 8-64MB of cache.
A new type of HD known as a solid state drive (SSD) is quickly emerging. It's cost per megabyte is significantly higher than a traditional HD but its transfer speed is also significantly faster. It can provide a massive boost in system performance if you have the extra cash to spend.
If you really want to up the speed you can go to a RAID 0 configuration. This will use two or more hard drives and alternates the bits between them, thus increasing your speed. The downside is that if one hard drive fails you loose all your data. A RAID setup can also be tricky to install, especially for first time builders.
There are a lot of extras that can go into a new PC. Some add functionality and some are just for looks.
A Blu-ray or DVD burner are great for backups of critical data. With SD cards becoming incredibly cheap it's nice to have a dedicated SD card reader in your PC for backups or making Raspberry Pi images.
Some extra fans are nice to have too. Most cases come with two fans but usually have mounts for several more. Usually more are unnecessary and just add to the noise but they can prove helpful in a crowded case. Unfortunately many cases come with cheap fans that only last a year or two when running 24/7 before they start to get loud or quit altogether. It's nice to have some ready to toss in down the road. Or if your just looking to build a quiet system you can pick out some special auto speed adjusting or low flow fans.
To add a special touch to your system you can purchase LED, cold cathode or EL lights. Laser cut fan grills or UV sensitive wiring are also popular if you have a case with a window.
Once you've made up your mind and have all the parts ready to go we'll move on to assembly...