How To Build Your Own Computer


Build Computer, Computing has changed a lot in the last decade. For many, smartphones have become the go-to method of playing games, staying in touch with friends, and browsing the Web for answers to spur-of-the-moment trivia questions and viewing cat pictures. When you need something more powerful, or with a bigger screen, you might reach for a tablet. And if actual, real work calls, the laptop you’d use is probably svelte, light, and stylish. Traditional bulky desktops are increasingly rare, and when you see them, they’re usually all-in-ones, or decked out with designs that are meant to be noticed. Let’s face it, no one really builds their own desktop PC anymore, right? (Build Computer)

Wrong, actually. DIY may not be all it used to be, but it’s still a thriving sector of the PC industry, and one that any serious computer user—we mean the type of person who cares more about what a computer can do than how small an envelope it can slide into—should be aware of. Because, if you want the strongest, most adaptable, most upgradeable, and most personal computer you can possibly get, there’s no way around it: You need to build it yourself.

By researching each individual component’s capabilities and limitations, you can tailor your purchases to your exact needs now and in the future. And if your requirements or your mood change tomorrow, next week, next month, or next year, you can easily pull out and replace as few as one of the pieces, and your computer is perfect for you yet again. Nothing else gives you this much control or satisfaction. Yes, you’ll have to sacrifice some—maybe a lot—of portability, but the result will be something you can totally and deeply call your own as you never will be able to with an unchangeable system designed and manufactured entirely by someone else.

Building your own PC is not necessarily an inexpensive or quick proposition. But if you’re willing to devote the time and resources to the project, you will end up with the best possible computer on Earth for you—and that will make everything else worthwhile.

Shopping for Parts
The most difficult and time-consuming part of the PC-building process happens long before you start looking for the screwdriver. You can’t even start thinking about assembling the individual components until you buy them—and that means doing a lot of investigating into the options (of which there are thousands) and, believe it or not, some serious soul-searching.

The first, and most important, thing to consider is: What do you want your PC to do? Are you looking for a really inexpensive system to put in the kids’ room? Do you want a squat, console-like desktop that will fit right next to the TV that you can use for streaming media, or maybe as a Steam Machine? Is a dedicated work PC for your home office the goal? Or do you want the biggest, baddest build that can play the hottest new games without breaking a sweat?

We can’t answer this question for you.  But once you’ve reached a decision, you’ll have a better idea of what you need to buy and how much money you’ll have to spend. And then you can get on to the actual shopping.

For research and shopping, we highly recommend using . It has a dizzyingly wide selection of components in every conceivable category and one of the Internet’s most powerful search engines for narrowing down your precise needs. But feel free to use your favorite tool (or brick-and-mortar store).

The nuances of what components do, and how to best get them to serve your needs, is beyond the scope of this story. But the descriptions below of their functions and what you need to look for when shopping should give you a solid of idea of where to start in collecting all the parts you’ll need for your PC.


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If you’re building a gaming PC on a budget, you’ll probably want to start off by choosing a video card (see below). But everyone else can start with the central processing unit (CPU), or processor, the “brain” of the computer that, well, processes all the instructions it receives from the software you run and the other components you have installed. Because of the considerable difference it will make in how well you run every program on your PC, paying particular attention to its capabilities is crucial. Here’s what to look for:(Build Computer)

  • Number of cores. Back when every CPU only contained one processing unit, or core, clock speed was the easiest way to measure performance. But practically every processor today is a multicore CPU, and the more cores a chip has, the more it can accomplish at once (if it’s supported by the software). Most common are two- (dual-) and four- (quad-)core CPUs, though six- and eight-core CPUs are becoming more visible on the market.
  • Number of threads. Most processors today, particularly from Intel, can simultaneously operate two processing threads per core (Intel calls this technology hyperthreading), effectively doubling your core count. Because not every processor supports this, check that yours does if you expect to be running a lot of multithreaded applications.
  • Clock speed (operating frequency). This is the frequency at which each core in a CPU runs, or the number of cycles it is able to execute per second. The higher the number, the faster CPU will generally be per core. These days, clock speed is measured in gigahertz (GHz), or billions of cycles per second.
  • Cache (L2 or L3). A processor uses memory installed in the chip itself to store and speed up operations before utilizing external system RAM. This on-board memory is stored in one or more caches, which are identified L2 or L3. More powerful processors will be equipped with larger caches.
  • Socket type. CPUs come in different sizes, are identified by the kind of socket they plug into. (For example, Intel’s most powerful current chips use the third revision of the LGA 2011 socket.) You’ll need this information to determine what motherboard to buy (see the next section).
  • Manufacturing technology. Every year or two, processors get thinner and more power-efficient. Knowing a chip’s manufacturing technology (measured in nanometers, or nm) will give you some insight into its capabilities, but is not strictly necessary.
  • Cooler. Most processors come with a fan rated for their specific speed and estimated heat output; unless you’re planning to overclock your computer or otherwise put it through particularly traumatic paces, you probably don’t need to buy another fan or liquid cooling system. (And for that reason, we’re not going to dwell on the question here.) But if you do decide to buy a separate one, or if you choose a high-end CPU that doesn’t come with its own fan, make sure that the cooler you get is designed for the family of processor you have or are planning to buy.


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If the CPU is a computer’s brain, the motherboard is its nervous system. Most of your other components will plug into the motherboard, so the one that you use for your build needs to be exactly what you need now, and what you expect to need from it in the future. Here’s what to look for:

  • Socket type. A motherboard’s socket type must, must, must match that of the CPU you plan to use in it.
  • Form factor. Motherboards come in a range of sizes, or form factors, from the tiny Mini ITX to the enormous Extended ATX. For most full-size desktop builds you’ll probably want either regular ATX or the somewhat smaller Micro ATX. The form factor you get will dramatically affect both the number of other components you’re able to install and what kind of case you’re able to install them in (see that section below for more details).
  • Memory. Be on the lookout for several different attributes of how your motherboard deals with memory. You need to know the memory type and standard, which are usually listed together. For example, if your motherboard supports DDR4 2133 memory, buy that. (Many motherboard manufacturers certify certain brands of memory for use with their boards; look up the motherboard on the Web to find out what’s officially supported.) The number of memory slots tells you how many individual modules, or DIMMs, you can buy; you’ll also be informed of the maximum memory supported, or the total amount of all the individual DIMMs taken together (such as 32 or 64GB). You may also see motherboards labeled as tri- or quad-channel, which signifies that you can expect a noticeable performance benefit if you fill the correct number of RAM slots. Note: Many times a motherboard will be listed as supporting a number of memory types with the designation “O.C.” after them—this refers to memory that is overclocked. If you don’t plan on overclocking your memory (which we don’t recommend, unless you’re an expert or fearless tweaker), you may safely ignore these numbers.
  • Expansion slots. The most common motherboard form factors, ATX and Micro ATX, will have between four and seven PCI Express (PCIe) slots, for adding expansion cards. These may use either the current top-end standard, PCIe 3.0, or the older (and slower) 2.0, with designations based on the size of the slots and the number of PCIe lanes they use. The longest slots are x16, though some that look identical may run at x8 or x4; in addition, there are visibly smaller x1 slots. On a Mini ITX motherboard, however, you should only expect one x16 slot.(Build Computer)
  • Storage. SATA remains the most common interface for connecting internal storage devices to your motherboard. The newest version of the standard, SATA 3, supports data transfer rates of up to 6Gbps. You may also find some other interfaces; M.2, in which a flash-based storage module plugs directly into a thin slot on your motherboard, is becoming increasingly popular, for example. Regardless, you’ll want to have enough of the right kind of ports for whatever storage you want to buy. (Learn more about that in the Storage section, below.)
  • Onboard technologies. Just about every motherboard will feature onboard stereo sound and Ethernet, most will include integrated Wi-Fi and/or Bluetooth, and many will also include ports for taking advantage of processors’ integrated video capabilities. (You won’t find the last on motherboards for higher-end processors, which are designed for use with discrete video cards, and you may ignore these ports on lower-end or midrange motherboards if you plan on installing a standalone video card.) It’s worth checking the specs so that you don’t forego something you really want.
  • Video card support. Think you may want to concoct an ultra-powerful gaming machine with more than one graphics card? Even if you have enough slots to hold multiple cards, you’re out of luck if your motherboard isn’t designed for use with either Nvidia’s SLI technology or AMD’s CrossFireX, so verify that first.


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Your computer’s random-access memory, or RAM, is where data is stored while the processor is waiting to crunch the numbers. More is pretty much always better, within the boundaries of your budget and your system (if yours is 32-bit, it’s limited to about 4GB; 64-bit PCs can handle up to 192GB, which is much more than any consumer desktop motherboard can currently hold), though if you use simple applications and aren’t an avid multitasker, you can get away with less. The nice thing about building your own PC: If it turns out you need more, memory is one of the easiest things to add. Here’s what to look for:(Build Computer)

  • Type. Memory will only be useful to you if the motherboard supports it; read that section for more information. Each new standard offers some additional speed and features, but not in all situations, so don’t feel as if DDR4 RAM, rather than DDR3, is an automatic must for you if you’re building from scratch.  Just remember that RAM is not backward-compatible, so DDR4 will not work in a DDR3 slot. The higher the number in a memory’s standard, such as DDR4 2666, the faster it generally is. Faster memory designed for the same slot type will work in a slower slot, but save yourself some money and don’t leave any performance on the table you don’t have to.
  • Capacity. DIMMs for each memory type come in a variety of capacities, so you can buy what you need and can afford. It’s best to buy at least one chip for each memory channel (three for triple-channel, four for quad-channel), and memory often comes in “kits” to make that easier; and we don’t recommend mixing and matching capacities within any one build. If you see a capacity listed as something like “8GB (2 x 4GB),” this means the total amount of RAM is divided up between a number of chips (in this case, two DIMMs of 4GB each, for a total of 8GB).
  • Memory timings. Most memory specs include a series of four numbers, separated by hyphens, that provide an at-a-glance way to tell how speedy the memory is. The first number, CAS latency (the amount of time between when the memory controller requests data and when it’s available) is the most significant, and may be listed by itself. The lower the numbers, the faster you can expect the memory to be.
  • Other specs. Error Checking and Correction (ECC) memory is intended for high-performance systems such as workstations and servers; you will need a motherboard that specifically supports this type of memory if you want to use it (and most ordinary users won’t need to). Voltage numbers give you specific information about how the memory uses power, with higher voltages typically meaning speedier RAM—but this is something only overclockers will really need to know.

Video Card

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Though integrated graphics systems are more commonplace today than ever, even the best versions in the latest processors can’t deliver what you can get from even a lower-end discrete video card. If you’re into gaming of any sort, a video card is a must, but any programs that are designed to take advantage of graphics hardware acceleration, from Windows to Photoshop and beyond, can benefit from offloading video processing to a dedicated subsystem. Unless you’re blasting out a tight-budget build, there’s no good reason to forego a video card. Here’s what to look for:

  • Processing cores. Like your CPU, your graphics processing unit (or GPU) has contains multiple processing cores exclusively for churning out graphics. The more of them your video card has, the better a performer it’s likely to be (and the more it’s likely to cost). AMD calls its versions “stream processors” and Nvidia has named its own “CUDA cores”—note that although you can’t directly compare the two types, the numbers of cores are good indicators of relative power within each company’s chipset families.
  • Clock rates. As with your CPU, this is the speed at which the graphics processing unit, or GPU, runs. It’s not unusual to see cards with fewer processing cores and faster clock speeds, or vice versa, so try to find the best blend for the amount of money you have to spend.
  • Memory. Video memory (VRAM) serves a function for video cards that’s similar to what ordinary RAM does for the rest of your computer: It stores the data until it’s needed for processing. This matters less if you’re playing at lower resolutions, where there aren’t as many pixels and other visual effects to be wrangled, but, as a rule of thumb—as with RAM—more tends to be better. (You’ll see 4GB or more on the highest-end video cards.) Also pay attention to the memory clock speed, which can also function into performance.
  • Ports. A video card isn’t worth much if it’s not hooked up to at least one monitor. Look at the list of its ports to determine whether your card outputs to DVI, HDMI, and DisplayPort; if you’ll be using your computer with a monitor you already own, you’ll want to know ahead of time whether you’ll need to buy an adapter. Another good idea is verifying how many monitors the card can drive at once: It may not be the same as the card’s number of output ports.
  • Power requirements. Video cards are among the most power-hungry PC components you can buy, so know what you need to get from your power supply. Usually there will be a minimum value you should respect, and you’ll also be told the specific number of PCIe power connectors (six- or eight-pin) you’ll need in order to get the card to work, as well as the number of amps needed from the power supply (see that section below for more information about this).


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Even if you love smartphones and tablets, you have to admit that storage is one of their biggest weaknesses: You seldom get that much, and you’re pretty much stuck with whatever you buy. When you’re building your own PC, that’s not a problem—it’s easy to add or change more pretty much anytime you want. But even if you don’t have to worry too much about capacity, you need to make a few other crucial decisions. Here’s what to look for:

  • Hard drive or SSD? The average price of solid-state drives (SSDs), which store data on flash memory, has dropped a lot in recent years, making them a better choice than ever to add to your computer if speed in booting up and accessing files is what you crave. But by and large, they’re still punishingly expensive on a cost-per-gigabyte basis compared with traditional, slower mechanical hard drives: It’s not hard to track down a 3TB hard drive that costs $100 or less, whereas consumer-oriented SSDs top out at about 1TB—and those will run you $350 at an absolute minimum. Because of this, the classic advice is still the best: Pair a lower-capacity solid-state drive (256GB or so is a good compromise), for installing Windows and your most important programs, with one or more spinning hard drives for housing all your data. Another option may be a hybrid drive, which stores most of your data on an inexpensive hard drive but uses a tiny amount of flash memory for things you use most frequently; this can save you a lot of money, but because of how the underlying technology functions, the performance will not always match what you get from a true hard drive–SSD pairing.
  • Interface. Serial ATA (SATA) connections are still common, especially for hard drives, and your motherboard will undoubtedly have plenty. But for major speed advantages, you can also buy newer SSDs on PCIe cards that install directly into your motherboard’s expansion slots and use that much faster bus. Other interfaces, such as mSATA and M.2 are less common, but you may want to take a page from space-saving smaller systems and consider M.2 (which plugs directly into a motherboard port) for use as a boot drive. Just be certain your motherboard supports whatever standard you intended to use.
  • Form factor. This refers to the size of the drive, with hard drives coming in 3.5- or 2.5-inch varieties, and SSDs coming in 2.5- or 1.8-inch models. For desktop computers, form factor doesn’t always matter much, though you’ll need to have the right kind of space in your case for whatever drive you choose.
  • Hard drive specs. A couple of extra details may appear on hard drive listings that you won’t see when researching SSDs. Most consumer hard drives spin at either 7,200 or 10,000rpm, with the speedier drives costing more and using more energy. You can also select the amount of cache memory your hard drive uses (up to 128MB) to boost performance. This information is useful for detail-oriented purists, but is of limited use if you don’t plan to use your hard drive as your boot drive (which, as mentioned above, we don’t recommend).
  • Is optical optional? Now that most software is purchased and delivered digitally, an optical drive may not be a necessity for you, particularly if you don’t plan to install a lot of older programs. If you don’t want an optical drive, you’ll need another strategy for installing the operating system; use another computer to create an installation USB key, for example. If you do want a drive, it may be worth it to splurge a bit on a Blu-ray burner (they cost around $100, or about five times what you’d pay for a DVD burner), so you can watch high-definition movies you may have hanging around.

Power Supplies

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You can buy the best components to be found on the Web, and they’ll be useless if you can’t actually turn your computer on once you’ve finished building it. A power supply unit (or PSU) may be the most unappreciated of components, but without it, nothing else will work, so don’t forget to give it the thought it deserves. Here’s what to look for:(Build Computer)

  • Maximum power. This is the highest amount of power the PSU is capable of directing to your components. The less complicated or intense the build, the lower a number you can get away with—for most people, 500 to 750 watts will be fine. But if you’re using high-end parts, particularly energy-sucking video cards (or more than one), your power needs could raise to 1,000 watts or even more. Checking your components’ power usage or thermal design power (TDP) is vital—get a power supply that’s too weak, and your computer may not even turn on.
  • Voltage rails. Simply put, voltage rails are like individual power circuits within your PSU, with each of the major varieties (+3.3V, +5V, and +12V) powering different kinds of components. In most cases, the most important one to pay attention to is the +12V rail, as that’s what will be driving your video cards; one of these capable of supplying 34 to 40 amps should be enough for the most powerful cards you can currently buy, and is likely to be more reliable than using multiple +12V rails for the same job.
  • Form factor. Like other components we’ve covered here, power supplies come in a variety of form factors that determine the kinds of hardware you can use with them, and under what circumstances. The most common for mainstream motherboards right now is the ATX12V, but you may also see others (such as EPS12V), and you may need to buy a smaller power supply if you’re building a system too miniature to fit a full-size ATX power supply, say.
  • Connectors. Power supplies come in two varieties: one in which all the cables are preattached, and another (called modular) that lets you connect only the cables you need. In either case, your PSU still has to have the right connectors, whether six- and eight-pin for video cards, SATA for newer hard drives and SSDs, or Molex for older drives and other devices. The good news is that if you don’t have all the connectors you need, adapters aren’t too tough to find. Still, it’s easiest to verify that you have what you need ahead of time; the PCIe connectors for the video card are most likely to trip you up, so find out what your card needs so your PSU can supply power in the proper way.


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Yes, you’ll need a case to house all the other components you buy, and that’s what we’ll focus on here. But remember that it’s also the outward expression of your computer’s personality—and your own. How big should it be? What shape? What color? Do you want a window? Make these decisions, too, so your final computer will look every bit as good as it runs. But as far as the necessary specs, here’s what to look for:

  • Form factor. Though a case can basically be as big or as small as you want it to be, what matters more is which form factor of motherboard it’s designed for. One intended for ATX motherboards will have room for the board and the proper number of expansion slots; a Micro ATX motherboard is smaller and will have fewer slots, though the case itself may not necessarily be smaller; and smaller form factors still, such as Mini ITX, may require other adjustments to your component choices (less storage, for example, or maybe a smaller power supply). Many larger ATX cases can also be used with motherboards of other form factors; as long as yours is supported, you should be fine.
  • Front-panel ports and controls. You’ll definitely want to access all of your computer’s features, and its front-panel ports are the way to do that. Every case will have Power and Reset buttons and an activity light, and most will also have headphone and microphone jacks and USB ports; some may even have fan or lighting controls. Just remember that you’ll need to connect any front-panel ports to the motherboard, so cross-comparing those specs ahead of time is a good idea.
  • Drive bays. You’ll need someplace to store your hard drives and SSDs, and any other devices you may be using. Generally speaking, cases may have one or more 5.25-inch external bays for optical drives other enthusiast gadgets, and multiple bays for 3.5- or 2.5-inch hard drives and SSDs. (Some cases also have externally accessible 3.5-inch bays for easily swapping hard drives in and out.) The smallest cases, though, can have very few of these, so pay attention, or risk not being able to perform necessary upgrades later.
  • Fans and filters. Cooling is one of a case’s most important functions. Your case will probably come with one or more intake or exhaust fans, and have room for adding more (in several sizes, from 80mm on up) if you want them. Removable filters, which capture dust to keep your PC’s interior tidy and are easy to clean, are also common on higher-end cases.

Putting It All Together

Once you’ve decided on and purchased your parts, it’s time to do the really exciting/fun/scary thing: assembling them all. Believe it or not, this is less difficult than it may sound, especially now that tool-free cases are de rigueur and you won’t need your Phillips screwdriver for installing much more than the power supply and the motherboard. But doing things in the proper order will help out a lot.

What follows is the basic procedure we used while building a higher-end system for testing hardware here in PC Labs. It illustrates most of the points you’ll encounter in your building, though the details will differ a bit depending on the components you buy. The basic techniques, however, seldom vary much from build to build.

1. Get Prepared

Just as a chef wouldn’t fire up the stove without the mise en place ready to go, neither should you. Unpack all your components, remove the packing material from them, and arrange them cleanly on a large, flat surface. The floor will absolutely work if that’s all you have, but try to avoid doing it on a carpet—static electricity remains a major danger for electronics, and frying your system before you even get to use it is one shock you don’t want. (If you’re concerned, you can use an antistatic wrist strap or ground yourself by touching some bare metal, such as the frame of your empty computer case, before you start working with anything else.) Also, open up the main side panel of your case, because that’s where your build will begin.(Build Computer)

2. Install the Power Supply

You won’t need the power supply until much later in the build process, but you’re better off installing it first because once the other components are in place, it becomes a lot more difficult to put the supply where it needs to go. Position the PSU in the bay with the fan pointing downward (many cases will have a vent there) and the screw holes lining up with the holes on the back of the case. Secure the power supply with the provided screws, then drape the cables over the side of the case to keep them out of the way while you work on everything else.

3. Install the Processor

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Most of the time, it’s going to be easiest to install some components on the motherboard before you put the motherboard in the case—you’ll have a lot more room to work that way. The processor definitely qualifies for this treatment. Begin by opening the socket. If you’re using an AMD CPU, just lift the lever to release the locking mechanism; you’ll also need to do this for Intel chips, but notice that a metal cover will also secure the chip in place, and that needs to be lifted as well. (On higher-end Intel chips using the LGA 2011 socket, two levers hold down the socket cover, and you’ll need to lift those one at a time.) Once the socket is opened, use the arrows printed on the socket and chip to align the CPU correctly, then lower it gently into the socket. (With AMD processors, the pins are on the CPU, so they’ll need to all go down into the proper holes and the chip sits flat before proceeding.) Once the chip is in place, secure the socket again by reversing the procedure you used to open it.

4. Install the CPU Cooler

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Some fans and coolers may come with the necessary thermal compound already applied.  If yours doesn’t, squeeze a small dab onto the center of the top of the processor; you can spread it around evenly with something like a business card if you want, but this isn’t strictly necessary. With most stock coolers, you just align the support posts for the cooler around the socket and secure them in place; each cooler is slightly different in this regard, so refer to its instructions for exact directions on doing this with the model you have. If you’re using a liquid cooler (such as the one shown in this paragraph) or another aftermarket cooler, you may need to install mounting hardware on the underside of the motherboard or configure a universal support mechanism for use with your specific motherboard and processor—either is another good reason to install the cooler while the motherboard is still outside the case.

5. Install the RAM

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The RAM bays are opened with the little clips at either end (some motherboards use only one set of clips, but most have two)—just push them down. Align the notch in the memory connector to the raised “key” in the RAM bay (you could do damage to the DIMM if it’s not oriented correctly), then push the DIMM firmly into place. When it’s correct, the clips should rotate back up and lock the memory in. Repeat with your other chips. Note: If you’re using multiple-channel memory, the DIMMs should be installed in the proper channels if you want the according speed boost. It’s pretty easy if, say, you have a quad-channel board and only four memory bays, but it might be more confusing in other situations, though the bays are often color-coded to clear things up. Consult your motherboard’s manual if you’re not sure.(Build Computer)

6. Place the I/O Plate

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Each motherboard comes with a specially designed I/O plate that labels each of its ports and helps close off the back of the computer from dust and other intrusions; you don’t absolutely need it, but it’s a really good thing to have. Align the plate right-side up (you may want to compare it to the back of the motherboard, just to be safe), place it inside the wide space at the rear of the case, and push on it—hard—until it locks into place on all four edges.

7. Mount the Motherboard

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Although some cases come with preinstalled motherboard risers, which prevent the board from directly touching the metal of the case, most don’t.  To find out where the risers should go if you’re not sure, place the motherboard in the case and see which holes in it correspond with which holes in the case, then screw the risers that came with your case into those holes.  (Some cases have the holes needed for the various form factors marked so you won’t have to either do this or guess.)  Once the risers are in, tighten each of them as much as you can. Guide the motherboard gently into the case, pushing its rear-panel ports through the correct openings in the I/O plate, and then laying the motherboard on top of the risers so you can see them through the screw holes. Insert and screw in half way all the screws; once they’re in, and you’ve verified that the motherboard’s position is correct, go back and screw them all in the rest of the way. Be careful not to overtighten the screws.

8. Install the Video Card

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The video card plugs into the longest (x16) PCIe slot on the motherboard, the first in the series of slots. Open that slot on the case, either by unscrewing the cover blocking it or utilizing your case’s tool-free mechanism. Line up the card’s backplate with the slot and the gold connectors (avoid touching them) with the slot itself. Then push the card down until it clicks. Secure the card in its position using whatever method your case employs. Note: If you’re using an extra-wide video card or multiple video cards, you’ll need to open more than one slot.

9. Install Your Drives

Because every case is different, it’s tough to provide a single blanket explanation for how to install the specific drives for your build. Most 5.25-inch drives, if you’re using them, will either screw in place or use a simple tool-free system on one or both sides of the drive cage. It’s not uncommon for 3.5-inch drives to install using caddies or trays, though they may also screw into a smaller cage below the 5.25-inch one (almost always at the top of the drive well). And many of those same trays will also have space for 2.5-inch drives, though some of these drives come with adapters that let them work easily in 3.5-inch bays, or other slots (such as on the floor of the case or beneath the motherboard tray) may be provided for installing them. Other drive form factors, such as mSATA or M.2, install into special slots on the motherboard itself; and still other drives can be placed in PCIe slots. The manuals for your motherboard and any unusual drives will have the information you need about this.(Build Computer)

10. Connect Your Cables

With all your hardware installed, it’s time to start linking everything together. Run data cables from your drives that need them to the appropriate ports on the motherboard. (SATA ports are often located along the edge of the motherboard.) Ensure that everything that needs power gets it: Connect the appropriate cables from the power supply to the motherboard (you’ll probably need two for this: one terminating in a 24-pin plug, another in a four- or eight-pin plug), to your video card (one or more of the six- or eight-pin cables, probably labeled PCIe), and to your drives (the connectors are thin and black). For bonus points, route your interior cables through the holes in the inside of the case and around the back of the motherboard if you can; most non-budget cases today are designed to facilitate this. Yes, the inside of your computer will look better (nice if you have a window), but you’ll also be improving airflow, and thus the way your computer deals with heat.

11. Connect Your Wires

The final step in making it possible to interact with all the various parts of your computer—and seeing that they operate correctly—is connecting all the wires.  Connect the power wires from your CPU cooler and any case fans to the proper pins on the motherboard; sets are clearly marked for “CPU Fan,” “Chassis Fan,” or “Aux Fan.”  Then connect the wires from the front panel to the appropriate headers: USB will be common here (note that the 2.0 and 3.0 standards’ headers look different), as will the headphone and microphone jacks (which will connect via the same audio header), but you may have other esoteric ones to deal with as well. Last, but not least, link the bevy of tiny front-panel wires linked to your activity lights and Power and Reset buttons to the pins on the motherboard. These are almost always labeled on the board itself, but they can be hard to see, and it can be difficult to know which of the two-pin connectors goes where. Again, consult your motherboard manual if you have any questions as to what goes where—you won’t do any permanent damage if you screw this up, but your buttons might not work and your lights might not flash correctly, and that can sometimes be even more annoying.(Build Computer)

12. Start Using Your PC

That’s it. You’ll still need to install Windows and software, and tweak the BIOS or UEFI settings to your liking, so there’s a fair amount of work yet to be performed. But remember that this doesn’t have to be the end of the process. Want more speed? Swap out the processor for a faster one. Tackle more demanding projects by upping the RAM. Make your games more exciting by replacing your video card with the latest and greatest model. Add another hard drive or two or three. The choice is yours, and you can change your mind at any time—and upgrading individual parts (aside from the motherboard) is invariably easier than starting from scratch. In any event, rest easy knowing that you’re doing it all on a PC you built especially for you, and that will always reflect your needs and desires in a way no tablet or laptop easily can. Sure, maybe a desktop is limited in some ways in 2015, but you’ll have more freedom than with any other setup. And don’t be surprised if you find that the satisfaction you derive from putting it all together yourself, is well worth the loss in mobility.(Build Computer)