How to Build a Custom PC: the Complete N0ob's Guide to Building a Computer




This Instructable will take you through the basic steps of building a computer. What you will need for this is:

~Computer Case
~Power supply (if not included with case)
~Hard Drive
~CD Rom drive/DVD Rom drive/Floppy Drive
~Modem/Ethernet card/Wireless card
~Extra Fans (if you would like)

Any input is welcome!

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Step 1: Get Your Stuff

I usually get most of my stuff online at New Egg, but you can get them at Tiger Direct or any electronics place. (It's a topic for another instructable, so I won't get carried away.)

Another great site for cheap parts, courtesy of mas-retals:

In general:
~Power Supplies
--->Make sure your motherboard is compatible with the processor you choose! (Socket AM2, etc.)
~AMD Processors
~Intel Processors
~Hard Drives
~CD / DVD Drives / Burners
--Make sure that your motherboard supports your drives' data interfaces (Serial ATA< Parallel ATA, or any other type, same with PCI and AGP devices)

Once you get your parts, make sure you also have:

~ Phillip's or flat head screw driver (The size of the screws on the outside of the case)
--This depends on the type of screws in your computer case

~Small head Phillip's/Flat head screw drivers
--For mounting the motherboard/hard drive/DVD rom/CD rom/Floppy drive

~Anti-static gloves
--May be unnecessary, but always be careful when handling delicate computer components, such as the processor.

Step 2: Install Components - Power Supply

This step is for those people whose cases did not have power supplies currently residing in their bare abodes.

First, you must switch the power output to your appropriate voltage. For America and Canada, the voltage is around 110 - 120 VAC at 60 Hz, but for Europe, you would set it to 230 VAC at 50 Hz. If you don't set this correctly, you risk frying your motherboard!

(Thanks to CameronSS and Phesarnion for the input about this!)

There are about four (4) screws you need deal with to screw it into your case. Just make sure that it's going the correct way (check the outside faceplate) and it's pretty much self explanatory from there.

Next, we'll move onto the motherboard.

Step 3: Install Components - Motherboard

The motherboard connects all of the PC together. It is home to the CPU and the interfaces for the disk drives and hard drives.

First, we want to mount the motherboard before we connect any wires or put in the processor. There are most probably four to six screws in the mounting.

After the motherboard is mounted, the next step is to insert the processor. Though it varies with technicalities, all processors generally are locked into place and then the heatsink is put on top of them to, well, remove the heat and prevent the processor from overheating. Instructions for installing both of these components lie inside their boxes, so check there if you need specifics.

Step 4: Inserting the RAM & PCI Components

To install the RAM (Random Access Memory, the amount of space a computer has to function), simply pull up the two fins and slide it in. Again, it varies from machine to machine, but always be gentle with these parts. They will break. A friend of mine broke his motherboard when trying to force the RAM into its slot.

The PCI components range from Ethernet cards to modems. A wireless card and a TV tuner card are being used in my demonstration. To put these in, you either need to take a cover off of the back (see pictures) or simply screw the card in after it's put in. Once more, be careful with the cards, but also MAKE SURE they are fully inserted.

AGP components are installed just like PCI cards, except in the AGP port. AGP cards are graphics card, while PCI and PCI express cards can be any type of component. You can check your motherboard manual to discern which slots are PCI or PCI express or AGP. Generally there is only one AGP slot.

Step 5: Installing & Connecting the Drives

Any 5.25" optical disk drive fits into the 5.25" drive bay, or the front section of the computer case. The hard drive, though, is connected in the lower drive bay (3.5") as opposed to the upper part where most internal drives are located. If you want to use an old school floppy drive, you'll most likely need to secure it in the smaller drive bay as well. The most common form of securing these in place is by using screws on either side of the drive bay.

To do this, you will need both case covers off so you can reach both sides of the drive bay. Simply slide the drive into place, whether it be DVD or CD, line up the screw holes with the holes on the drive bay, and tighten the screws in place. In my demonstration, I only use fours screws per drive.

As for connections, the white connectors with four large holes in it them are the power cables that plug into the optical and hard drives. Also plugging into the hard drives are ATA data cables (either serial, which are the small black cables, or parallel, the older wide cables)

Step 6: Extra Ventilation & Finish

In my case, I wanted to make sure my computer was cool enough because there wasn't any fan blowing in cool air/extracting hot air. I picked up a fan at my local Micro Center and screwed it into the holed area on the back of the case. I then hooked it up to a molex connector with the adapter included and was done.

Finally, you can plug in the rest of the power cables to the motherboard. After this, screw up your case, plug in the power, monitor, mouse, and keyboard, and get ready to install an operating system. (My next Instructable).

Step 7: Your Custom Comps!

blckpythn -
'"'i built my first computer a little over a year ago
and im just now upgrading it
i now have 1gig of RAM
an AMD athlon 64-bit x2 4300+ 2.4ghz
EVGA GeForce 8600 256mb
and with the new processor i also got an Arctic Cooling Freezer 64 Pro
~i also have 240 gig hard drive"

hondagofast -
"I built a perfectly good computer with:

A Dell Optiplex GX240 mintower case that had a 250W PS and a motherboard with a 1.6GHz CPU (bought at a garage sale)
1gig of DDR memory
A 120GB Maxtor drive (very old and slow) and a 40GB Seagate for backup
A DVD-ROM (now dead)
A DVD/CD burner (dead, don't buy cheap products people!)
A Creative Soundblaster Audigy
A Nvidia GeForce 4200
A USB 2.0 card
A U.S. Robotics Wireless card

The case I have opens like a clamshell and is easy to work on, it just doesn't have any space for extra fans..."

"I am a bit of a geek overlord myself. My most powerful self constructed computer has 2 quad core xeon processors, 8 gb memory, and 2 tb hardrive(s) 2gb video cache, 12 usb 2.0 ports, 4 dvd dual layer r/w and 2 floppy. It took me 3 years to complete it.

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201 Discussions


Im going to use this to biuld my gaming pc this summer!

Also, Mesaynaysayer/, Yes. Linux is great...not for gaming, though.


4 years ago on Introduction

We were recently cleaning through a storage unit. I came across what appears to be an old half-built server. It is not completely built so I am looking to finish building it. It is custom built, so there are no stickers or modal numbers that I can see. It has 4x 1gb ram chips. Two hard drives (with room for three more), fans, processor, and dvd drive. I knew how to insert the ram chips but I don't know how to connect all the power cables inside. I'm hoping to find instructions some place. I could use some help. I have done some computer programming, so I know what the parts look like and function to some degree but not enough to put this together. I don't want to risk damaging it since it may be worth a lot more than a 10+year old pc. I don't think there is an operating system loaded, and I'm not sure how to go about that either. Any suggestions?


5 years ago on Step 7

um... im not using ubuntu Linux because i would like to have a gaming computer. For a gaming computer i would use Microsoft Windows 7 or XP. Just Saying

1 reply

Reply 5 years ago on Step 7

Linux is having a much stronger adoption lately than it has in previous years, especially with the upcoming Steam Machines. Additionally, XP should never be used for anything due to its end of support being 6 months ago.


5 years ago on Introduction

The best custom PC building guide ever, The screen shorts and procedures make it so simple to understand by a lay man. I really appreciate it ;) See more about A custom PC Here


7 years ago on Step 3

No Standoffs? Most PSU's come set at the appropriate voltage.


7 years ago on Introduction

Really good information. I read this and I really considered building my own PC. I would've if I didn't find out about I priced the parts that I was going to get compared to what they had and it was only $70 more not including the $20 off promotion they have if you do an unboxing video and put it on YouTube. So for $50 I get a professionally built computer, 4 year warranty, and lifetime technical support.

There is nothing wrong with building your own PC, if you do then that's great for you, but for the money I wanted to put into the PC I honestly felt more comfortable having a professional build it.


8 years ago on Step 7

wow!!! that's really cool! :D
man, I'm new to all of this stuff and it was actually my math teacher who introduced the class to how much cheaper it is to make your own computer than to spend like $700+ for one that someone else probably spent like 79cents a piece! Could you give me some cool suggestions for places to buy these products?


8 years ago on Introduction

wow you know there was a article in pc world a wile ago i might use there pc and bulid one


9 years ago on Step 7

I built my own computer around two years ago (counting from 2010) and that's what I am still using. When I built it I had about the latest hardware at that time (Intel Core 2 Duo, 160 GB HDD, 2 GB Ram, etc.), now I discovered that my system is already outdated. This is the problem with computers, once I had to change my motherboard and I couldn't find the same model again. Luckily I found another one which was compatible with my processor, and I didn't have to re-install the os since I use linux (Ubuntu, for those of you who know more about linux). I didn't really build a custom computer since it was the first one I built.

8 replies

Reply 8 years ago on Step 7

oops.. didnt mean to say "top of the line", meant to quote you saying you used the "latest hardware"


Reply 8 years ago on Step 7

Um... 2008, they had quad cores, most 400$ computers had 4gb of ram and at least 320GB hard drives.... Sorry, not top of the line, even for 2008


Reply 9 years ago on Step 7

Ubuntu rules :D. your comp was outdated, but worked as long as it works and is still reasonibly fast your ok lol, in my books anyway


Reply 9 years ago on Step 7

Well, Linux has the good thing that it doesn't have (almost) any driver problems, so I could change my motherboard with no problem, and the computer isn't really too old (2 years), but what I mean is that everything evolves really fast!


Reply 9 years ago on Step 7

You have more Driver/Software problem with Linux than with windows . i repair computer all day long and i never had any problem with windows , the problem with linux is that some driver dont even exist for some hardware . ohh , and linux is useless if you want to play game , and no i never had any problem with virus and i am using windows since windows 3.0.


Incorrect on both facts: Linux has more drivers then windows, and with WINE and play on linux you can run any game you want.

Exactly! And Linux has MUCH better plug and play support, when I bought my printer I just had to plug it in and it worked, no driver installation.


Reply 8 years ago on Introduction

yeah , it is why i was never able to connect on the internet with my Wifi key , even with the help of all your "community".