Tips and checks for buying a used MacBook

Apple's MacBook systems are stylish and quite popular, but also come at a relatively steep retail price that may be too much for some people. While Apple offers discounts for refurbished systems, another option people have is to purchase a system second-hand from someone who has upgraded their older system.

While new and refurbished Mac systems come with a one-year warranty and 90-days of free technical support, this likely will not be the case with a used system, so if you buy one you will need to be sure it is working properly.

MacFixIt reader Nooruddin recently wrote in with such a concern:

"I am looking forward to buying a pre-used MacBook and my question is what should I look for when I am buying a used Apple laptop? I would generally check for its config and price, but is there a way I can find faults in the computer (like life of the hard drive, RAM, screen, battery etc.)?"

Buying used computers can be a hit-or-miss situation at times, but there are a few things you can do to ensure the system is working and does not need repair.

First, be sure you have an option to test the system before you purchase it, or at least have the ability to return it if there is a problem. Also be sure the system comes with its recovery DVDs (these should be gray discs that were shipped with the system), especially if the system did not originally ship with OS X Lion. These discs contain a hardware test that should be run on any used system you are considering buying, and also contain the OS version that shipped with the systems and should be kept with them.

When you go to see the system for the first time, be sure to bring the following items if you can:

1. A working USB and FireWire hard drive (preload it with a fully updated version of OS X if you can -- at least use Snow Leopard, but OS X Lion is preferable)
2. A robust drive management tool like Drive Genius or TechTool Pro (you can also preload this on the external hard drive)
3. An external headphone
4. An external microphone
5. A movie DVD and a music CD if the system has an optical drive

With these items available, you are now ready to test most of the system's functions properly and check it for problems. You can do this fairly thoroughly using the following steps:

1. Check its age
   While Apple's systems should work fine for years, be sure you are purchasing the system that you intend. Apple's systems can look quite similar, and therefore be difficult to distinguish, so a system from 2009 will physically look like a more modern one from 2011. Apple has a couple of resources that will help you in identifying various Mac models:

   How to identify a MacBook
   How to identify a MacBook Pro
   How to identify a MacBook Air

   
   In general I recommend people avoid systems that are more than three years old, but these specifics depend on the user's needs and the prices being offered.

2. Is there any physical damage?
   Check the system thoroughly for physical damage. Check the screw heads that hold the case together to see if someone has stripped or marred them at some point, which may indicate they were too rough on the system when replacing RAM or a hard drive. While dings and scratches happen at times and don't usually indicate a problem, be sure the case isn't severely warped or bent. The display lid should close and match up evenly to the bottom case, and the system should not have any rattles or loose-feeling components in it.
   
   In addition to obvious physical damage, check the display hinges. The MacBook displays have a clutch mechanism that should keep the display open at any supported angle, especially if the system is on a flat surface. If the display falls shut or open and will not stay without being propped up, then it is likely it was tampered with or abused at some point.
3. Does it boot?
   Be sure the system boots up fully. The system should make a boot chime when you press the power, and then boot fully to an OS X installation (the speed of this process will be different depending on the system, but it should load to an OS X desktop). If OS X is not installed, then you can use your external hard drive preloaded with OS X to boot the system and test it out (hold the Option key at startup to select the boot drive).
4. Is a firmware password set?
   Apple's systems support a hardware-based password, which if enabled will prevent the system from booting to Safe Mode, Single-user mode, and perform other tasks that can aid in both the configuration and troubleshooting of the system. While the password can be reset on some systems by removing a hardware component such as RAM and then starting the computer, Apple has made this more difficult in its recent systems. Therefore, ensure the firmware password is disabled when you purchase the system. To test for a firmware password, start up the system and immediately hold the Option key after you hear the boot chimes. If the system shows a boot menu with available boot drives and arrow buttons then there is no password set; however, if it displays a password prompt with a lock icon then the password has been set.
5. Check the display
   Next, open a word processing document so you have a white surface to move around on the display, and use it to check the screen to ensure all of the pixels are working properly (be sure to scrutinize corners and edges). You might have an easier time checking each RGB component of the pixels by using a program to draw a pure green, blue, and red box and then move them around on the display. If a pixel is not working properly, then it should stand out as a darker or different colored spot. While sometimes a dead pixel or two is unavoidable, if there are groups of stuck pixels then that is clear indication of a problem.
6. Check the keyboard
   Next check the keyboard by using the same document to type each key character and ensure it works properly. You can also open the system's keyboard viewer panel to ensure each key-press is properly registered, which will help for non-character keys like the function keys, escape key, and modifier keys.
7. Check the trackpad
   Next check the trackpad and ensure it makes a proper click when you depress it, and also that it tracks smoothly. Sometimes over time trackpads can wear out and take barely any pressure to invoke a click, and result in a trackpad that constantly selects things or clicks buttons. Apple's multi-touch trackpads are made of glass, and while they are relatively difficult to break, sometimes this can happen and result in a crack that sometimes can be easy to overlook, so be sure to check the edges and corners of the trackpad.
8. Check the FireWire, USB, and audio ports
   Attach your external hard drive to each USB and FireWire port on the system and ensure it is properly recognized. Do the same for headphones and the microphone jack, to ensure they work and automatically switch the input source or output source when a device is attached (open the Sound system preferences to see these switch behaviors and test the microphone setup). In addition to testing an external microphone, test the internal one as well.
9. Test the iSight camera
   Apple's MacBooks come with an iSight camera at the top of the display, which can be tested by launching Apple's Photo Booth program.
10. Test the optical drive
    Use your DVD and CD to ensure the optical drive reads them properly, and optionally try to burn a blank CD or DVD. You can use the Finder to burn a few files quickly by dragging them to the inserted blank media and clicking the burn icon.
11. Battery health
    Next check the battery by going to the System Information utility and go to the Power section. In here you will see a "Health Information" section with a cycle count and condition status. Generally Apple batteries last between 300 and 1,000 charge cycles (see here for model-specific cycle counts), and while a lower cycle count is generally best, this is not always the case. Batteries do best by regularly keeping electrons moving to ensure they do not build dead spots. If someone has always kept the laptop plugged into wall power or has stored it in a completely discharged state for a while, then the battery may have a low cycle count but also may have lost capacity.
12. Drive errors
    Use Disk Utility to check the drive for errors. Check its S.M.A.R.T. status in Disk Utility (at the bottom of the Disk Utility window), and also use it to verify both the filesystem structure and partition map health. Unfortunately hard drives can often hide areas of corruption and other potential problems, especially in the few minutes you might spend in assessing a system. If you have access to a robust drive testing utility like Drive Genius or Tech Tool Pro, then you can have it check the drive for errors more thoroughly. However, if not then it's not the end of the world. Ultimately if the hard drive is corrupted and needs extensive repair, then you can replace it with a new one (though this might affect your negotiated price or your decision to buy).
13. Test system settings
    For some MacBook systems, Apple includes two graphics processors. Go to the Energy Saver system preferences and then run the system with the "Automatic graphics switching" option both checked and unchecked, which will toggle between the two GPUs. Open the System Information utility and ensure in the Graphics/Displays section that the system's "Color LCD" switches between the different graphics cards when you change these modes (you will need to refresh the information window's view by pressing Command-R when changing modes).
14. Hardware tests
    Lastly, while the system may appear to be OK after performing these tests, there may be some underlying issues with hardware sensors and components that may not show up when briefly testing the system. To test these, Apple includes a hardware testing suite with its systems that comes either installed on the hard drive, included on the gray recovery DVDs that came with the system, or as an Internet download option on some of Apple's more recent systems.
    
    The hardware tests will output an error code if various sensors, fans, or other components are not working or over or under a threshold limit, and will also check the system's RAM for any errors. While the tests offer an extended RAM check that should be performed, this can take a very long time to complete, and the basic RAM test should be adequate for most situations. See this article for how to invoke and interpret the Apple Hardware Tests.

If any of these tests show problems or failures, then consider looking elsewhere for a system. In some cases like a single stuck pixel or even a hard drive error, the problem may be tolerable or fixable, but this determination is up to you. When all of these tests are done and you are certain the system is OK for purchase, then be sure to fully wipe it and reinstall a fresh copy of OS X to the hard drive. Doing this will ensure the system's software environment is as new as possible, and will allow you to configure it according to your needs, instead of managing someone else's setup.

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