How to use old parts to build a new PC for free

Ah, the joy of summer storms. A recent one involving a flooded basement (a torrential downpour traveled down a chipmunk burrow that led to an otherwise enclosed basement window with a broken windowpane) and several staccato blackouts sent one of my neighbor’s computers, as well as one of my own, to their eternal rest.

Fortunately, I had two spare computers — one for me and one for the neighbor. I bought a few uninterruptible power supplies and we were back in business. But now I had no spares left, and that’s simply not acceptable for a card-carrying geek.

Problem was, after buying the UPSs (and fixing the basement) my disposable income was pretty much disposed of. But I had parts! After almost 30 years of playing with computers, I’ve accumulated a lot of stuff: motherboards, monitors, modems, processors, memory, graphics cards, TV tuner cards, drives (CD, DVD and hard — both internal and external), cases, keyboards and mice. I think there’s even a Bernoulli Box sitting on a shelf somewhere.

Step by step

True, some of my collection (which was stored in that basement) met a sad end during that same storm. But I was pretty sure that I still had enough parts left to put together at least one complete computer.

Turns out I was right — and any self-respecting geek should be able to do the same. What follows is a step-by-step account of how I put together a new computer from old parts at a bare minimum cost.

One disclaimer before we begin: My motherboards tend to be from Asus, my DRAM is from Crucial Technology, and my cases and power supplies are usually from Antec, so you will see those names appear quite a bit among my parts choices.

We could launch a debate as to whether or not these companies are actually the best of the best, but they are companies whose products have given me, personally, the least grief. Your experience may vary. Don’t be afraid if it does.

Choosing the parts

Even though I was just creating a spare computer, I wanted it to be a good one. It wasn’t enough to simply cannibalize the first box of parts I came to. I wanted to end up with a PC that, if not bleeding edge, could be used without embarrassment.


When it comes to real estate, the important thing may be “location, location, location,” but for a computer, it’s “motherboard, motherboard, motherboard.” You can easily build a computer based on a junk motherboard just for the satisfaction of saying you did it (for example, I have an MSI 486 ISA motherboard with an Opti chip set and memory installed, and I’m sure there’s a compatible CPU around here somewhere), but intrinsically the result would still be junk.

The P5N-E SLI motherboard.

Of the four motherboards I had on hand, two were too old for anything but Internet appliances, and one, a relatively new Asus M3A78-EMH I purchased back in May, is destined for a forthcoming HTPC system build. The fourth, an Asus P5N-E SLI, seemed to be the best choice. The P5N-E SLI is an ATX motherboard I’ve had for over a year.

It was pulled from a system that died; it turned out that the problem really was a three-month-old hard drive that crashed and not the motherboard at all.

Incidentally, if you haven’t retained the original installation disc for your chosen motherboard, this would be a good time to visit the manufacturer’s Web site and download the appropriate driver for your operating system.

Processor and memory

Having given the P5N-E SLI the nod, I knew that I’d need an Intel processor and memory coordinated for that motherboard. Luckily, that didn’t present a problem. Typically, when I pull a suspicious motherboard, I yank it out as a unit with the CPU and memory installed (in the case of the P3N-E SLI, that meant a Core 2 Duo E6700 CPU and 2GB of Crucial DDR PC-4200 memory).

That immediately removes those two components as potential problems on the replacement motherboard. With this motherboard cleared of fault, it gave me a complete platform ready to go. The only thing missing was a heatsink/fan for the CPU, which I pulled off one of the two older motherboards.

Graphics card and TV tuner

Your graphics card can limit or enhance the overall performance of your computer. I had several older cards, some going back to a Rage Pro in an NLX (PDF) form factor.

The Radeon X1600 Pro graphics card (left) and the Nvidia DualTV MCE tuner card (right).

But the best of the bunch was a Radeon X1600 Pro. In its day, it was a good performer without the top-heavy price tag. Right now, it’s a nice low- to midrange graphics card that’s a bargain when it’s free. (All right, even if you had to buy it, you’d only be spending $70-$100 if you were smart. That’s still cheap.)

I happened to find an old Nvidia DualTV MCE tuner card wrapped in a freezer bag right under the X1600. (I managed to get two of them in the six weeks between when I was impressed by the first one I bought and when Nvidia canceled them.) It’s analog, but the tuners are good and Cablevision has promised to take care of me (and everyone else) when we change to digital broadcasts in February 2009.

Hard drive

For some reason, the bulk of my spare hard drives are Parallel ATA (PATA). It might have something to do with the increasing acceptance of Serial ATA (SATA) as a valid performance enhancement. As I use up space on my drives, I clone the data onto larger, newer devices and then stash the old ones. As a result, I had a 500GB Maxtor PATA drive sitting in the pile. It was the right drive for the system.

The 500GB Maxtor PATA drive (right) and the Asus DRW-1814BL optical drive (left).

Optical drive

I only had one spare optical drive: an Asus DRW-1814BL. It’s not bad, even if it is a LightScribe drive. (Using special DVD discs, you can print a label on the disc itself if you have some — OK, a lot — of spare time to kill.) The Asus, however, was a PATA drive and so it would need to share the interface with the hard drive. That could be a problem — as I found out later, few, if any, cases are built to pair 3.5-in. and 5.25-in. devices effectively.


Because the Asustek motherboard I decided to use was an ATX-sized board, neither of the two micro ATX cases I had on hand would work.

The Antec P180 case I selected is literally last year’s model; it’s been replaced by the Antec P182. Still, the original has sound-deadening material on the side panels, three 120mm fans (which I had previously expanded to a fourth) and lots of drive bays. Its bottom-mounted power supply setup is an acquired taste, however.

The Antec P180 case has a drive bay arrangement similar to most cases: the 5.25-in. drive bays are way up here and the 3.5-in. bays are way down there. This presented a problem: I wanted to seat a 3.5-in. hard drive as the primary unit and a 5.25-in. optical drive as the secondary.

The Antec P180 case.

There was a three-in. space between lowest 5.25-in. bay and the highest 3.5-in. bay. Four and a half inches separate the connectors on the average PATA cable, which may seem like enough to span the bay gap. It’s not.

Why? Because going with the existing bay structure meant that the 3.5-in. hard drive would become the second device on the cable and the 5.25-in. optical drive the first. Conventional wisdom is that your fastest drive (the hard disk in this case) should be the first device.

I could have done that here by twisting the cable around a bit, but if I did, the distance between the two connectors would decrease with the twist and they would no longer reach their respective drives.

A 5.25-in. bay adapter (so that the 3.5-in. drive could go into a 5.25-in. bay) was an option, and I did have one on hand (naturally), but personally, I prefer a bit more panache. I found a used Antec Hard Drive Cooler in one of my new K-Mart plastic storage boxes of spares.

The HD Cooler is basically an aluminum platform with side rails and a front panel into which the drive is installed. The cooler then mounts into a 5.25-in. bay, solving the distance problem. And that front panel isn’t just a pretty face: it’s used to alternately report the temperatures measured by the cooler’s two sensors. Typically, I tape one to the drive and one to the power supply.

Power supply

Power supplies are often a cause of concern. We’ve been trained to “go big” no matter what. Even when, decades ago, it was shown that a computer could run reliably at under 100 watts of power, some pundits scoffed. Today, with higher-power processors and graphics cards, that’s no longer the case — we really do need a lot of power. Still, how high do we need to go?

The three power supplies available.

Among my basement stock, I could choose between a 350-watt Phantom 350, a 430-watt NeoPower 430 and a 500-watt SmartPower SP-500 — all by Antec.

Back when I first got the Phantom, it was an interesting premise: no fan, just a giant black heatsink wrapped around the electronics, and, of course, no fan noise. By the time I got around to building the system it had been intended to power, a multiplicity of hard drives and a graphics card that needed its own separate power line moved it out of contention.

The initial build of this computer will be rather light by my usually building specifications: midrange CPU, low-end graphics card (by current standards), one hard drive and one optical drive.

The Phantom 350 could easily handle the initial few components without breaking a sweat, and do it silently. However, I have plans to add a pair of 15K Cheetah SAS drives and a Promise Technology SAS controller in the near future, and that will take more power.

The NeoPower 430 would probably have done the trick, but I decided that the SmartPower’s 500 watts would be better in the long run, especially if I then decide to add another DVD burner and SATA hard drive or two.

(Note: If I do load this system up, over time you might find that I’ve switched to one of Antec’s 80 Plus power supplies. There are two new models, the Signature 650 and the Signature 850 (the numbers tell the power rating.) These are both designated as “Bronze” units (think Olympic medal order of importance), meaning they’re 82 per cent or more efficient at 20 per cent, 50 per cent and 100 per cent of load.

With nine computers in perpetual motion in my house, it’s something I’m seriously considering for a general upgrade.

Most importantly, when you’re dealing with a bottom-mounted power supply — new or old — be absolutely sure that the cables will reach everywhere they need to go. That’s especially true of the CPU power connector that’s typically at the top of the motherboard, two virtual football fields away from the power supply unit (PSU) down at the bottom of the case. Measure twice, cry once.


Did you know that I have four spare LCD monitors in 15-in. to 22-in. sizes? I didn’t know I had them, either. They were boxed and stuffed into one of the corners of the garage.

(One of the more troubling things about being a computer geek is that you also save almost every box that once housed your equipment. You never know whether you’ll need to ship an item back or, as in this case, just stash said product in the garage when it’s reached its point of obsolescence.)

The Optiquest monitor sits up front.

The group included Optiquest, Princeton, Samsung and SYS displays. The SYS monitor was the first LCD I ever purchased, with built-in speakers and a stuck pixel from the factory. In this case, I went with the 22-in. widescreen Optiquest Q22wb. Optiquest is Viewsonic’s “popular” (read “lower cost”) brand of monitors.

Operating system

My initial impulse was to install Vista Home Premium on this system. At the time, Newegg was selling a version for resellers for $99. (Vista is not the hardware ogre the press makes it out to be; in fact, for media fans who do a lot of TV recording and editing, it’s probably the best operating system that Microsoft has developed to date.)

However, this was supposed to be a free build. I dug up an ancient copy of Windows XP Professional (it was underneath the XP Home disc, which was underneath the Windows NT Workstation disc) and while I dreaded the 3.4 years I’d spend downloading updates, I decided to give it a try.

What, you may ask, about Linux? Unfortunately for those of us trying to pinch pennies, when it comes to legacy motherboards, there are copious drivers for Windows XP and a substantial number for Vista, but precious few for Linux. In fact, Asustek has no listed Linux drivers for the P5N-E SLI.

I was told that this shouldn’t be a problem, since Linux will usually take up the slack. Unfortunately, a little nosing around on a few Linux forums brought not a few tales of woe regarding the onboard audio and LAN functions. Just the same, I equipped myself with live discs of PCLinux 2007, Mandriva and Ubuntu to try.

Assembling the system

What I offer here aren’t, strictly speaking, step-by-step instructions. I’m going to assume that you know the basics of actually mounting a hard drive or attaching a motherboard. (You don’t? Then a good idea is to get an experienced friend to help you with this.) These are tips based on what I experienced while assembling my computer from a variety of disparate parts.

Before you start, it’s always a good idea to make sure you have all the tools you’ll need. Luckily, very few tools are actually needed to build a computer — and if you need to drop a few dollars to pick one up, be assured that you’ll use it again.

These should prove helpful: a Philips screwdriver (preferably with a magnetic tip), a wire cutter or nipper (don’t worry, it’s for lopping off the end of cable ties, which you should also have on hand), some compressed air in a can, a small flashlight or some task lights, and either a magnifying glass or pair of “hands-free” wearable magnifying glasses.

OK, you’ve got your parts, your tools and a couple of hours of free time. Ready? Let’s begin.

1. Case prep

After you’ve removed both the left and right side panels, place the case flat down on a table or workbench and start tucking wires out of the way. Don’t worry about where you put them right now — tape them to some innocuous spot if you have to. What you’re trying to do is clear the motherboard tray of anything that might hinder your slipping the board into place.

2. Motherboard logistics

The motherboard sitting in place.

“Standard” ATX motherboards often show up in slightly different sizes. The P5N-E SLI, for example, eschews the usual nine mounting points for just six to accommodate its somewhat narrower width.

The extra silver standoffs seen peeking out along the right side of the board won’t contact any of the circuitry or solder joints underneath, so I’ve left them in place. If you find that not to be the case when you test-fit your motherboard, remove any unused standoffs under the board that might cause an electrical short.

3. Mounting the drives

Even if you’ve figured out how to get the faceplates off the front of the case, it’s not necessarily a victory. Most good-quality cases have a secondary metal faceplate behind the case’s façade. They’re put in place to reduce radio frequency interference.

The secondary metal faceplates.

For the P180, these metal plates twist along the horizontal axis and are held in place by two small tabs, one on each side. It doesn’t take much force at all to twist these plates back and forth until the tabs break. Don’t worry if the plates fall into the case. They drop down to a platform at the bottom of the 5.25-in. bays and you can retrieve them when you’re done.

4. Primary wiring

With the motherboard and drives installed, it’s time for the primary wiring session. This includes connecting all of the cables routed from any top- or front-mounted ports (usually USB, FireWire and audio) as well as the front panel controls and LEDs (power-on, reset, power-on light, hard drive activity light and so on).

Learn which wires mount to which pins.

The front panel wiring (the multicolor ribbon cable in the picture) requires that you refer to the motherboard manual to learn which wires mount to which pins. I usually just print out that particular page from the electronic version of the manual (often found on the install CD or the vendor’s Web site) so I’m only fumbling with a single sheet of paper.

A good flashlight or task light is a must because you’re actually sticking your hand and head into the case to do the job and you’re probably going to block most of your ambient light.

5. Mounting the power supply

This is the moment when you meet the worst grief of the entire build. In the case, my P180 not only had the standard mounting screw positions at the back of the case, but it also had a cage for the PSU that needed to be removed first.

Once you’ve removed the cage and placed it on top of the PSU, start routing the power cables up into the center of the case. This is impossible to do with the power supply installed.

With the cables partially routed into the system, start jiggling the power supply into place.

With the cables partially routed into the case, you can start jiggling the power supply into place while pulling more of the cable through the hole in the partition. It’s not really that difficult to do if you keep your wits about you and your eyes on how the PSU is sliding into place. For the P180, I needed to re-install the four screws at the bottom of the four corners of the cage plus the four screws that hold the power supply to the back panel.

(In the picture, it looks like that main trunk of power supply cables is right against the lower fan hidden by the black mount. It’s not. The fan itself is recessed three-quarters of an inch further forward, and that’s more than enough breathing room.)

6. Drive cables

One of the great things about the P180 case is that I could remove both banks of 3.5-in. drive bays during the assembly. If you have ham-hands like mine, removing the upper bay can give you better access to the IDE connector (the blue one is the primary on this motherboard) so you can connect your PATA drives.

7. Tying it all together

Reviewers often give system sellers a hard time about how poorly they’ve managed to bunch all of the cables in a computer together and out of the way. Somehow, the standards tend to slip when the tie-wraps are in the other hand. As you can see from the photo, this didn’t turn out to be a work of art, but it is a work of me. Everything is in its proper place, nothing will wander out of the case, and so it passes in-house standards with a wink and a nod.

Not a work of art, but it works.

8. It’s alive!

No matter how good a builder you might be, there’s always that split second of abject panic that strikes just as your finger reaches out to press the power-on button. It encapsulates a cavalcade of scenes in your mind’s eye showing you what you did do, what you could have done and perhaps what you should have done.

Often, those mental images culminate in a small atomic cloud straight out of Dr. Strangelove mushrooming up just after finger and button meet.

However, the only way to prove one’s prowess is to actually power up the system … so I did.

It’s alive!

A loud moaning immediately filled the room. It was horrific. It would have sent me into a tizzy had I not immediately realized that it was one of the four fans that were installed in the case. It took a couple of seconds to localize the noise to the fan in front of the upper-drive bay — the one I’d scrounged from the parts bin, rather than any of the three that were pre-installed in the case.

The noise stopped after a few minutes once the fan bearing (or what I think was the fan bearing) had worked itself in (and yes, the fan was still turning).

But that’s only a temporary fix. At some point in time, that fan will seize up and stop. Right now, there’s nothing in front of it to cool — the bays are vacant — so it really doesn’t matter. I’ll be changing it when I add the SAS drives. (Not all old parts are good parts.)

Just a note on operating systems: It turned out that the Linux Live CDs ran the system just fine, so Linux was an option after all. But I’m a Windows fanboy from before Version 1.0. As a result, PCLinux 2007 just didn’t feel right. Ubuntu had a better GUI but seemed a bit slow. Mandriva was the best of the three (at least when measured with a Windows yardstick), but I still couldn’t get comfortable.

I guess you really are what you geek. Windows ended up as the operating system of choice.

The final tally

This system was free, collected from a variety of parts bins, boxes and drawers spread out across two rooms and a garage. Of course, you could actually go out and buy the parts, but that could get expensive. For those of us who have the capacity and the time to do it ourselves, keeping a good selection of spare parts seems to be infinitely cheaper.

If you bought the parts …
What if you didn’t have the parts in your basement or back room? Building this system could get expensive. If you include everything that I have, it comes to a grand total of $1,213 — a bottom line that comes in above quite a few prebuilt systems.

Antec P180 case $135

Intel Core 2 Duo E6700 CPU


Asus P5M-E SLI motherboard


2GB Crucial DDR2 PC 4200 RAM


Radeon X1600 Pro graphics card


Hauppauge WinTV PVR 500 TV tuner


Antec 120mm case fan


Optiquest Q22wb LCD


Logitech keyboard


Microsoft Mouse


Windows XP Professional


Of course, if you went the Linux route, you could chop $114 off that amount, bringing you to $1,099. And if you were smart, you’d pick up an Intel Core 2 Duo E7200 instead of the E6700 and pay $125 rather than $321.

That would bring things down to $903. And if you wanted to, you could forget the TV tuner and subtrack another $145 — although I wouldn’t. (I’ve substituted an equivalent Happauge tuner for the Nvidia, which has been discontinued.) That means your do-it-yourself system would come in at a less painful $758.

Would you recommend this article?


Thanks for taking the time to let us know what you think of this article!
We'd love to hear your opinion about this or any other story you read in our publication.

Jim Love, Chief Content Officer, IT World Canada

Featured Download

Jeff Radecki
Jeff Radecki
Web designer and developer of IT World Canada. Skilled in WordPress, Photoshop, mobile, SEO, and social media.

Featured Story

How the CTO can Maintain Cloud Momentum Across the Enterprise

Embracing cloud is easy for some individuals. But embedding widespread cloud adoption at the enterprise level is...

Related Tech News

Get ITBusiness Delivered

Our experienced team of journalists brings you engaging content targeted to IT professionals and line-of-business executives delivered directly to your inbox.

Featured Tech Jobs