How we refurbish a desktop computer

Posted on: Thu, 04/25/2019 - 11:27 By: charm


When buying a computer people want a computer that works well and looks good. Building a computer today is much easier than 25 years ago when technicians needed to know about setting jumpers for the right IRQ and DMA. Still, the process one person uses can vary a lot from the process another person uses. What follows is a list of steps we use to refurbish a computer. Our volunteers follow a checklist of steps. A checklist ensures everyone building a computer performs the same basic steps. Checklists also make it easy to troubleshoot steps that might have been missed. Along with the checklist we bundle a specifications sheet outlining what's inside the computer (but this doesn't get filled out until further in our process). It's worth mentioning here that we use a different process for refurbishing laptops, though some of the process is similar.

The Basics

When building a desktop computer volunteers need 3 things:

  1. The desktop computer
  2. A build checklist - this checklist has the steps we take to refurbish a computer
  3. A specifications (spec) sheet

Our refurbishing project stores desktops that haven't been worked on in our storage area. We currently have a minimum build specification of a Core 2 Duo-based system with at least 4GB of RAM and a minimum of a 160GB hard disk drive. Although Windows 10 can be quite slow on this minimum specification, Xubuntu Linux (our other install target) is quite usable. One of the simplest ways of identifying a system is by the stickers on the front or side of the system.

Desktop with a sticker that identifies the CPU as an Intel Core i7

The Checklist

We have separate build checklists depending on whether you're building a computer that will become a Windows computer or a Linux computer. All checklists are divided into several categories:

  1. Computer Externals - the steps in this category help us determine whether the computer is even worth building. Steps include things like making sure the computer isn't too broken/dirty to clean, whether it has bad capacitors, or is missing something important for it's operation.
  2. First Boot - check to make sure the computer POSTS (Power On Self TestS)
  3. Computer Specifications - record the details of what's in the system and upgrade anything that's needed to meet the target specifications for the computer (more on this below).
  4. Memory Test - test to ensure the RAM in the computer is good.
  5. Hard Drive Test - Any drives in a desktop should be removed and given to the volunteer responsible for wiping hard drives. They will give you a wiped drive to put in the computer. All hard drives should pass the short SMART test and have less than 50,000 hours. Any drives over this amount, regardless of whether they test good, should be put in the drive recycling area.
  6. OS Installation - At this point either Windows or Linux is installed on the computer.
  7. POST-Installation - After the installation systems are checked to see if all drivers are present and if everything is operating smoothly.
  8. Quality Assurance - This step is conducted by a person other than the person building the computer. QA steps check the work of the first volunteer looking for things like bad capacitors, dirt, cable management, whether the DVD drive works, if the BIOS is set up correctly, and if the specifications of the system are appropriate for the system.
  9. Sales Preparation - Assigning a price and labeling the computer, putting the computer into the Point-Of-Sale, assigning a MRR Windows license (if applicable).


In each of these catgories there are several steps outlined below. This is by no means an exhaustive list, but the minimum amount of work we want to ensure is done for each machine.

Computer Externals

The computer externals step is done to ensure the computer is worth building. Please be sure to step through each step on the checklist and put your initials beside each step:

Make sure the case is not broken, too dirty, or missing parts.

Open the computer and check for bad capacitors. Capacitors someones show brown liquid leaking out the top or bottom, and sometimes simply bulge up/down.

Leaking capacitor on motherboard

Test the 3V battery with the multimeter. The red (positive) lead goes on top and the (black) ground lead goes on the bottom of the battery. The battery should read 3V or higher. Batteries less than 3V should be replaced with a new battery. (New batteries often measure at least 3.27V). The multimeter should be set at 20V DC (don't set it less than 3V).

This 3v lithium battery measured 2.92 volts

Clean dirt from inside the computer using the air compressor, brushes, and rags. Brushes can be used on the motherboard, but rags should not be due to the fact that they're more likely to conduct electricity and short out the board. Clean the inside bottom of the case with a rag and use brushes in tight spaces. For really dirty computers be sure to use the vacuum end of the air compressor first so dirt doesn't blow up in your face. Safety goggles and masks are available in the plastic tool cabinet near the CR work area. The air compressor we use is a Metro Data Vac (we paid roughly $250 CDN from the same source a few years ago, this listing shows it at $450):

Very dirty PC - we wouldn't clean this PC, it's better suited to our ewaste stream

Remove any asset tags that identify the previous owner. Asset tags are often found on corporate donations, are usually metalic in nature, and often contain a slogan like "Property of ..." Also remove any personal stickers added by end users, stickers that might identify a company, or stickers that would not have been a part of the computer when it was new. Please DO NOT remove COAs (Certificate Of Authenticity) stickers as we use these when reporting MRR Windows licenses. Also please be sure to keep Serial Number stickers used by the manufacturer to identify computers. On Dell and HP computers this is sometimes called the Service Tag.

Clean the outside of the case, use a brush to remove dirt between plastic, use the air compressor on ports (USB/HDMI/etc), and use a damp cloth on the outside of the case. For difficult to remove stickers use a little Goo Gone (orange). Goo Gone works best if it has a chance to sit on a sticker for 2 minutes, but please be sure not to use the Goo Gone on the entire case as it tends to be very oily and it's expensive to buy in large quantities. (There is a yellow Goo Gone on the market as well, but in our experience the orange Goo Gone smells much better and seems to work better).

Make sure any empty slots at the front or rear of the PC are covered. We want the PC to look as complete and professional as possible, leaving empty gaps in the PC doesn't look good.


First Boot

Ensure SMART (for hard drives) is enabled in the BIOS. Not all BIOS's have a SMART feature, but please check the drive area of the BIOS and enable it if SMART is an option. SMART reporting will cause a hard drive to report when it thinks it's about to fail.

Set the boot order to boot from NETWORK/PXE first (all our software tools and installers work via a PXE server). If you do not see this available as an option in the BIOS please check the BIOS to ensure that the Network Boot ROM is set to ENABLED. Often the Network Boot ROM is disabled in most BIOS'. After you've enabled the Network Boot ROM you will need to save/restart and get back into the BIOS in order to set the Network/PXE boot option to the first spot.

While the computer is on ensure all fans are operating correctly and no wires are interfering with the operation of the PC.


Computer Specifications

Boot to the network server, you will see a "Danger, Danger screen." This is our PXE server where we have all our tools and software installers store on.

Press the F7 key to access the Live Environments menu. Type in debian-live to access our live Debian GNU/Linux environment. We have special software we use in this live environment to conduct a variety of tests.

Click on the icon that says Phoronix Test Suite, this will open a terminal window showing the specifications of the computer. Record the specifications of the computer on the "Specifications" sheet. If there are missing parts, like RAM or a hard drive, refer to the minimum build specifications sheet to put the proper amount of RAM and hard drive in the computer.

Running phoronix-test-suite on an AMD A8-5600K-based system

Confirm the computer meets our minimum specifications to build: currently this is a Core 2 Duo with 4GB of RAM.

Remove any 2TB+ hard drives as we use these in the shop.

If the system has a hard drive, remove it and put a wiped drive in the computer.

Make sure all cables are connected properly.

Close the case and replace any missing screws.


RAM Test

Boot to the network server, you will see a "Danger, Danger screen."

Press the F2 key and run memtest5. If memory fails: isolate the bad RAM stick, mark it as ewaste, and replace it with another stick, then retest. Computer Recycling uses Memtest86 to test RAM. Many Linux distributions include Memtest86 in the initial boot/install menu.

A failed memory test using Memtest 5.0

Ensure all RAM survives one "pass" of Memtest sucessfully.


Hard Drive Test

Boot to the network server, press the F7 key, at the new menu type: debian-live or debian-live-x64. Click the disk-tester icon. Double click on the hard drive icon. In the new window that pops up select the Perform Tests tab, leave the test type as short self-test and click Execute. The software we use is a Linux tool known as gsmartcontrol. We like gsmartcontrol because it can be used to run SMART tests against a drive, because it lists how many hours use a drive has, and because it sometimes shows when there are hard drive firmware updates.

Ensure the drive passes, If not replace it and label the old drive with a BAD label and put the old drive in the ewaste drives bucket.


OS Installation

Boot to the PXE server. Depending on whether you're installing Windows or Linux this next step will vary. For Windows press F9 Windows Autoinstallers, for Linux press F4 Linux Autoinstallers. If you're installing Windows the next step will be to type w10-v2 at the next menu screen. If you're installing Linux type autoinstall-cr-xubuntu-bionic-x64. At this point our autoinstallers take over and you can go for a coffee or take on another task (we recommend testing RAM/drives or sorting donated items). Installation takes anywhere from 20 minutes to 1 hour depending on the specifications of the computer and what's being installed. Our installer includes extra software both for Windows and Linux operating systems.

During a Windows installation the computer reboots relatively early in the process and may go back to the "Danger, Danger" PXE network boot screen. If it does this go into the computer BIOS and either turn off network booting or set network boot to be the last step in the boot process. Similarly, after Linux is installed the computer may return to the "Danger, Danger" PXE network boot screen. Disable network booting in the BIOS or set it to a lower priority in the boot process.

Post-Installation Setup

For both Windows and Linux the first step will be to check and see if the computer has all the necessary drivers. The process is slightly different for each operating system, but ironically you can just type "drivers" into the search bar field of each OS to bring up what you need.

In Windows you might see devices marked with a yellow circle and black question mark. These are devices Windows doesn't have a proper driver for. If you add any drivers to Windows please make sure you are downloading the from the manufacturer of the motherboard (for onboard devices) or the device itself (AMD video cards for example).

In Xubuntu Linux you might see "no restricted drivers available." If this is the case then Xubuntu doesn't see any devices it has a proprietary driver for. Generally, this "drivers" program is used to install devices for which there might be a "proprietary" driver for - such as wireless cards or NVidia graphics drivers. In the case of the NVidia graphics driver it's generally desirable to install the proprietary driver because it helps with gaming and overall display performance.

The next step is to check that sound works. You can test sound by plugging a speaker (or headphones) into the system and playing something from a streaming web site such as Youtube.

It's also important to test all ports on the computer. Sometimes computers come in with damaged or faulty USB ports. If a system has a physically damaged port it should be relegated to ewaste (pull the hard drive first). It's worth mentioning here that KVM switches (switches used to allow more than 1 computer to use a single keyboard, mouse, and video display) sometimes cause issues with USB ports failing or not functioning. If you plug a USB flash drive into a port and receive a message try setting up the computer without a KVM switch. We find it handy to test USB ports using a USB mouse.

While we bundle recent updates in our installers, both Windows and Linux installations almost always need to be updated after the installation. As with drivers, you can type update into the toolbar/panel of each respective OS to access the update installers.

Lastly ensure any other media devices are checked (play a movie in a DVD drive, insert an SD card in a SD media reader).

This is the last step a volunteer normally takes during the build process. From here the computer is set aside to be checked over by another volunteer using the Quality Assurance steps below.

Quality Assurance

The following steps should be done by a volunteer other than the volunteer who built the computer. The idea here is to check for things another volunteer may have missed, skipped, or not thought important. Look for things that might interfere with the operation of the computer, or might be problematic. This would be a very long list if we listed everything that could possibly go wrong. Sometimes hardware passes our software test, but is faulty nonetheless. An example would be a hard drive that passes SMART test but clicks, or has over 100,000 hours use. Another example of a problem not listed here are loose cables that might interfere with the CPU fan.

Open the computer and look for bad capacitors. While open check to make sure cabling isn't too messy and that the computer is clean. Can you run your finger on the bottom of the case and not pick up dust? Does everything look seated properly in its slot?

Does the outside of the computer look clean? Have all unwanted stickers been removed from the case?

Is the specifications sheet complete? If the system has a discrete video card is it listed on the specifications sheet? Are the RAM and hard drive sizes appropriate for the computer? (For example: a 1TB hard drive is appropriate in a system with a Core i7, but not a Core 2 Duo).

Has the BIOS boot order been set appropriately. Hard drive first, then other boot forms (ensuring faster boot).

Does the DVD drive play movies? Do all the USB and audio ports work correctly?

An important step that sometimes gets missed is filling in all empty case slots at the back of the computer. Please be sure that all slots at the back are covered with a slot cover.

Sales Preparation

Any volunteer can do the sales preparation steps for a Linux computer (including the volunteer who originally built the computer), however all Windows computers have to pass through STAFF who affix the new Windows 10 license to the system. Sales preparation steps include:

(WINDOWS - STAFF) Run sysprep.exe from the desktop and select the GENERALIZE option.

(WINDOWS - STAFF) Generate the MRR PDFs for the machine using the portal.

An example of the MRR PDF generated for the Microsoft licenses

(Linux / WIN - ALL) Look up the system price from the price sheet and generate a price sticker using our barcode printer. (We use a Zebra LP2844 printer. At home I use a Dymo LabelWriter 450. The problem with the LabelWriter 450 is that labels are expensive when compared to the Zebra LP2844. Labels for the LP28440 range in price, but we normally pick our labels up for around $100 CDN for 15,000 labels, compared to a bit less than $50 for less than 1,000 labels.) For Windows use the template COMP0007, for Linux use the template COMP0006. Please do not save over top these templates as we've set up the proper sizing for each label in these templates.

(ALL) Affix the price sticker to the front and the top of the machine and on the PDF print out.

Enter the machine into the POINT-OF-SALE system.

Place the machine on the sales shelf.

Notes: This article is constantly being updated. Please check back frequently for updates.