There are two ways to find the right components. a) based on COMPATIBILITY This is a very important part. If just ONE component is incompatible with your computer, then it can possibly mean chaos for all the other parts in a computer. For example, do NOT try to force a 204-pin memory module (used for Macs) into any ATX or mATX motherboard with a 240-pin memory socket! Also, you need to get a CPU that is compatible with the socket on the motherboard, a power supply that can power your graphics card, etc. 1) CPU compatibility Warning: Spoilers inside! First off, make sure your motherboard has a socket which is compatible with the maker of your CPU. For example, get an Intel motherboard for an Intel CPU. The socket of your CPU also matters. Example: get an Intel LGA 1155 CPU for an Intel LGA 1155 socket motherboard. 2) RAM compatibility Warning: Spoilers inside! Please, don’t try to go overboard with the RAM. 4GB should be enough for practically everyone, even gamers! (Most 32-bit systems have 4GB as a limit) I recommend that you get memory sticks that are about 1333Mhz. Ivy Bridge can only handle 1600Mhz, and Sandy Bridge with 1333Mhz. 3) GPU compatibility Warning: Spoilers inside! This partly depends on what YOU want. If you want an entry-level card (like an NVidia GeForce GT 430), the only requirement is a PCIe x16 slot on the motherboard and a power supply that gives a total of 300+ watts of power. If you want a performance graphics card, like an NVidia GeForce GTX 690, you need a PCIe x16 slot, a power supply with a total of 700+ watts of power, and a power supply with 2 graphics card power connectors. 4) Motherboard compatibility Warning: Spoilers inside! This will have to do with the case. Normally, a mATX or ATX motherboard will fit in an ATX case, but an ATX motherboard will not fit in a compact mATX case (for obvious reasons). Though there are other motherboard standards, ATX and mATX are the most popular ones. 5) Case, hard drive, 3.5 inch device (card reader), and 5.25 inch device (fan controller, optical drive) compatibility Warning: Spoilers inside! This all needs to be compatible with the motherboard, and/or the power supply, and/or the case. I recommend you get a motherboard with at least two USB 2.0 headers (for an optional card reader and front panel USB ports), and 2 SATA ports (for an optical drive and a hard drive), AND a power supply with SATA power (for the hard/optical drives) and one 4-pin Molex power (for the *ahem* optional fan controller) connector, and a case with at least 2 5.25 inch external drive bays and 2 3.5 inch external drive bays. Also, make sure your motherboard has the proper front panel connectors for your case (such as power button, reset button, etc.) 6) OS Warning: Spoilers inside! I suggest Windows 7 Home Premium for compatibility and everyone. It gets almost every job done at a great bang-for-the-buck. b) based on who you are First, identify yourself as either: a) a guy who checks email and types in Word all day b) a busy workaholic who is busy all day on the computer c) a slight gamer who plays less-demanding, medium-intensity games at 70+ FPS d) a gamer-for-life who demands to pwn n00bs at 200+FPS in very-high intensity games Even though I’m stating the obvious, I’m gonna say it: your identification of one of those four options differs your needs from others. For the guy who checks email all day, I recommend you don’t build a computer at all and just buy a ViewSonic VOT125 mini PC or any netbook/tablet. For the busy bee: I suggest you get one of a mid-class NVidia graphics card (such as the previously mentioned GeForce GT 430). From personal experience, I know NVidia is better at making budget graphics cards than AMD/ATi. For the CPU, get an AMD CPU like this one. It costs cheap but has power. For the slight gamer like I am, get an i5-2500 or better with a mid-class NVidia graphics card, like the one I mentioned before. For the BIG gamer who demands 200+ FPS in high-intensity games (and I'm not kidding. Just please be comfortable with spending a lot): I recommend you get 2 NVidia GeForce GTX 560’s and a motherboard with 2 graphics card slots and one that supports SLI and supports 2-way SLI. Also, get 1 SLI bridge. An Intel i5-2500K should suffice for the CPU, but get an adequate CPU cooler with it. Oh...and a power supply with 4 GPU 6+2 pin power connectors and one with at least 800+ watts. And a case that has really good air flow. I hope this helps you find the right components in your new PC build. P.S. Watch this video if you need more assistance, and feel free to leave comments and questions below.