Overclock.net › Articles › What Goes Inside a Computer

What Goes Inside a Computer

Most OCN members have been building computers for years and know all about hardware, but there are also new members that perhaps may have never built a computer before. In this guide, we will be looking at what parts you need to build a computer. Everyone has to start somewhere, so you may as well learn the basics here.

The Basic Parts of a Modern Computer:

Case: This is the most visible part of the computer. The case is the part that houses all the other components. Several things to consider here are the color, style, what size motherboard that it can hold (form factor), placement and number of fans, and how many drives it can hold. Bigger cases can hold big motherboards (such as the EATX form factor) and more drives while smaller cases can only hold small motherboards (mATX) and less drives. Not only should you look at the size of the motherboard that will fit, but also consider the heatsink that you plan to use on the processor. Check the manufacturer's website to be sure that you have proper space to fit it when the side panel is closed.

Power Supply: As the name implies, the power supply is the part of the computer that sends power out to all of the various parts. Most power supplies are a certain size, but high-end power supplies may be a little longer, so check with your case to make sure that it will fit. One thing to consider is the noise output. If your power supply unit (PSU) has a huge 120mm or 140mm fan on the bottom, then it will probably be fairly quiet. However, it you have a PSU with a single 80mm fan, it may be significantly louder. Other things to consider are the total wattage that it can supply and how many amps it can provide on the 12 volt rail(s). It's better to over-estimate how much power you need rather than under-estimating it. Also, be sure that the power supply that you are buying comes from a reputable brand such as Corsair or Seasonic. The PSU that you choose should also have enough connectors to connect all of the various components that you plan to use, with the ability to add more in the future.

Optical Drive: Optical drives include dvd burners, blu-ray drives, etc. Basically, any drives that read from or write to a disk. The thing to consider here is the speed at which it reads or writes.

Solid State Disk / Hard Drive: These are used to store your programs. For years the hard drive has been the storage unit of choice due to its low price and high capacity. If you plan to install your operating system (OS) and performance oriented programs such as games on it, then a speed of at least 7,200rpm is recommended. However, if you want it to be quieter and plan to only use it for file storage, you may want to consider a slower 5,900rpm drive. For those who want top performance, solid state drives (SSD) offer a significant speed increase over slower mechanical hard drives and they are also silent. If you are buying one of these, it's also important to consider a reliable brand and to note whether it uses the SATA2 or SATA3 (faster) interface. A common storage configuration is to store your OS and games on a SSD while storing your music, videos, and other files on a larger hard drive.

Sound Card: This part is optional since most motherboards come with a built-in sound card. However, using an aftermarket sound card can provide less distortion, higher sound quality, and more features. When buying a sound card, be sure to check that your motherboard has the appropriate connector. Most modern sound cards use the pci-express interface while older sound cards just used the pci interface, which is slowly being phased out.

Video Card: For a gamer, this may be the most important part of the computer. The video card renders everything that you see on the screen. Some motherboards have a built-in video card, but using an add-in video card will give you a significant performance boost. When buying one of these, the most important feature is the GPU used. A video card with a high-end GPU with less memory may perform better that a lower-end GPU with double the memory. However, make sure that whatever video card you buy has enough memory to run modern games. I would recommend a minimum of 1GB. Also, if you plan to use several video cards to enhance performance, be sure that your motherboard has enough pci-express slots, your power supply has enough wattage and connectors, your processor is fast enough so that it doesn't bottleneck the performance of the cards, and that your case has proper airflow to keep them cool.

Motherboard: This is the heart of your computer. Everything is connected to it and it will determine what parts you can use. Things to look out for here are: 1. What processor socket type does it support? 2. How many connectors does it have? (Sata, Usb, etc..) 3. What chipset does it use? 4. Does it have enough of the pci/pci-e slots that I may need in the future? 5. What is the form factor (size)? 6. How much ram can I add? The motherboard's socket type will limit what processors that you can use and may impact your upgrade-ability in the future. Smaller mATX motherboards have less expansion slots than full sized ATX boards, so also keep that in mind.

Memory (RAM): Before a program can be executed by the processor, it must be stored somewhere. It would take too long to retrieve the data from your hard disk or SSD, so a small amount of high-speed memory called RAM (random access memory) is used to hold programs that are current being executed by the processor. Things to consider here are capacity, voltage, timings, speed, type, and the heat speaders used. If the heat spreads (the colored covers on the memory sticks) are too tall, they may prevent you from installing some larger heatsinks onto the processor. As far as capacity, I would recommend that a modern computer have at least 6GB-8GB. There are several types of memory, but most modern computers use DDR3. Lower voltages are better, as they provide less heat and suck less power. The timings of the RAM affect the latency, or how responsive they are. Lower is better, but under real world conditions, it won't make a huge difference unless your are benchmarking. The speed also affects performance and higher is better. However, as longs as you have a certain speed (for example DDR3-1600mhz), going above that speed won't make a huge difference unless you are benchmarking.

Processor: The processor (CPU) is the brain of the computer. This part executes all the programs that you run. The type of CPU that you can use is limited by what socket your motherboard accepts. Generally, higher speeds and more cores are better. However, different CPUs from different manufacturers or from different generations may perform differently, so don't compare two CPUs based on these two numbers alone. For modern gaming computers, it is recommended to have four cores. If you do media encoding, photoshop, or other things of that nature, you may benefit from hyper-threading or having more cores. Hyper-threading is basically when a processor tricks the OS into thinking that is has twice as many cores. To quote wikipedia: "For each processor core that is physically present, the operating system addresses two virtual processors, and shares the workload between them when possible." It can lead to a performance boost, but the software that you are using must be able to take advantage of it. Games usually see little to no benefit from hyper-threading.

Cooling: As computers get more and more powerful, it becomes increasingly necessary to make sure that all of the parts are sufficiently cooled. The main parts of the computer that require cooling are the processor and the video card, but you should also make sure that your case has enough fans to keep air flowing across the components and to prevent heat from building up in the case. In most cases, air should flow in though the front and out through the back and top. However, some unique cases such as the Silverstone Raven 2 pull in air from the bottom and exhaust it from the top. Just remember - as air becomes hot, it rises. Most video cards come with sufficient cooling already installed, but you may want to upgrade if you want a higher overclock or less noise. Most processors come with a heatsink, but you are usually far better off by buying an aftermarket heatsink. If you plan to overclock the processor, then this is a requirement. Make sure that the heatsink you choose offers the performance you need at a price and noise level you can tolerate. For additional CPU cooling, you may consider adding a second fan to your heatsink or even upgrade to water-cooling. However, I highly recommend that everyone start out with air cooling while learning the basics.

Now you should have an understanding of the basic parts of a modern computer. With the knowledge of what's inside the computer that you're using, hopefully you now have the confidence to build your own. Building a computer can be a very fun, educational, and rewarding experience.

Comments (2)

Well documented the fundamental assembly process of a system in simple language. It reminds me my first day in computer class about hardware. I crashed two systems in a single day and my punishment was not to touch any system for next 30 days. But that couldn't kill my experimental attitude. password manager
Nice and fluant documantation. Thanks a lot.
Overclock.net › Articles › What Goes Inside a Computer