This is the most common problem. All laptop batteries deteriorate over time soexpect to replace the battery unless the seller guarantees that the battery can hold a charge or that a new battery has been installed. When your laptop arrives download and install the free version of CPUID HWMonitor. The original battery capacity, the current capacity, and the current charge level are shown at the bottom. I would not sell a laptop with less than 85% of the original capacity.
If you only use your laptop with the charger plugged in the battery condition is not all that important, but don't use it without a battery unless it's plugged into an uninterruptible power supply. A power glitch could crash your system and cause you to lose whatever work you haven't saved.
If you see "no battery" it means one of two things: either the battery is bad and the seller doesn't want to bother replacing it, or the motherboard has problems, in which case you don't want that laptop. Ask questions.
If you have to buy a new battery, the most cost effective method is eBay. Find an eBay seller with thousands of feedback ratings, close to 100% positive, and who is willing to accept returns. Many of the listings that scream "Genuine Brand New OEM Battery" and charge the highest prices are bogus. They look real but they're actually crap from you know where that won't take or hold a charge. One giveaway is screw holes that don't line up with the ones in the laptop. Many of the most expensive batteries I've bought have ended up at the recycling center either because they couldn't hold a charge or because they were incompatible with the power supply and/or motherboard.
The alternative is Amazon. You'll pay more and you're just as likely to get a bad battery but Amazon is very good about returns. You can drop them off at your local UPS store. They will pack, label and ship your return for free.
Missing Hard Drive (HDD)
If you see "no hard drive (HDD)" it means one of two things: either the seller is afraid that you might recover the embarrassing content of the hard drive or that there never was a hard drive to begin with.
People who keep secret and/or illegal materials on their computer are afraid to let the hard drive out of their hands because they believe that formatting it or reinstalling Windows isn't safe enough and that wiping it thoroughly (overwriting every bit multiple times) takes too long. Most of the time, "no HDD" is actually good news. You don't want Windows running from a hard drive. It's easy to install a new solid state drive and reinstall Windows as long as a stupid seller hasn't also removed the caddy (the frame that holds the drive in place), the SATA connector, or any other part that has to be replaced to make the system work.
Some sellers don't understand that a laptop never had a hard drive to begin with. An SSD may look exactly like a 2.5" hard disk drive or may look entirely different (see Solid State Drives). Some computers are sold with an SSD in addition to a hard drive or only an SSD. Some SSDs look like small circuit boards and are covered with protective material. Some laptops have an optional extra-large battery instead of a secondary hard drive. Make sure you know exactly which model of laptop you're considering and what kind of storage options it had originally. It's easy to find detailed reviews of laptops.
No Operating System
You may see listings that say "No operating system, boots to BIOS, etc." This is typically a result of the hard drive having been pulled and is generally a non-issue. You can install and activate a fresh copy of Windows. It's quite easy:
On another computer, go to microsoft.com and create a Microsoft account, unless you have already done so. Make note of your username and password.
On another computer, download and run the Media Creation Tool and create your own installation flash drive or DVD. Don't worry about having a Windows license.
On another computer, search for your new laptop and find the function key needed to enter the boot settings page.
Insert the flash drive or DVD into your new laptop.
Boot the laptop while holding down the key that enters the boot setting page.
Select the flash drive or DVD you just inserted.
If the procedure asks whether you want an upgrade installation or a custom installation, select custom and delete any existing partitions on the SSD (or the hard drive if you don't have an SSD).
When the procedure asks for identification, use your Microsoft account.
Missing Memory (RAM)
If you see "no RAM" the laptop may be okay but be very careful. There's only one good reason to pull the memory out a laptop that you intend to resell: it has more than it needs. For example, it's common to pull the memory from a laptop with 32GB of RAM and replace it with 16GB or even 8GB. If you intend to buy new memory, only buy from one of the established memory websites. They have databases that can tell you exactly what kind of memory you need. I've always had good luck with Crucial.
Most laptops have two memory slots. If it's advertised as having 16GB it almost certainly has two 8GB cards. Only use identical memory cards. Never mix sizes or manufacturers.
This can mean almost anything. The only thing you can assume is that the laptop won't boot or has had parts stripped out. Read the description carefully. You can get a very good deal if you know how to replace missing parts but be careful. A bad motherboard generally means that you've wasted your money.
All laptops slow down over time unless maintained carefully. Most software products eat up bits of your memory by starting automatically, checking for updates automatically, installing "helper" programs, and by installing unwanted browser plug-ins and toolbars. It's a good idea in general to wipe the system drive and reinstall Windows. To prevent memory degradation use reliable system maintenance software such as Advanced SystemCare and IObit Uninstaller. I also recommend Driver Booster to make sure there are no obsolete device drivers on your system.
Bad pixels look like tiny white or light grey spots or clusters of spots.A few may be acceptable if you're not fussy but if you're paying for a perfect screen you should get a perfect screen. Use this dead pixel test to find out. Left-click or use the space bar to change colors. If you see too many dead pixels return the laptop.
Check every key on the keyboard, including all the function keys, with and without holding down the Shift key. You may find some that are loose or require too much pressure.
Defective or Unbalanced Audio
Make sure the audio is balanced and clear in both channels. Use the audio software that came installed on the system or the Windows Sound applet in Control Panel. Test the built-in speakers, the audio inputs and outputs, and the microphone input jack.
Defective or Intermittent USB Ports
Test each USB port by wiggling the cable. If you can cause a glitch, it will probably happen by itself at some point.
Obsolete Communication Protocols
Make sure the machine supports the same versions of Bluetooth and USB (or Thunderbolt) as those in your external devices.
All laptops get warm and some laptops can get quite hot when they're working hard. This is normal and particularly true of "gaming" laptops with high-performance graphics processors, but there's a limit to how much heat is safe and comfortable. When the temperature of a CPU or GPU gets above 90 degrees Centigrade, you should be concerned and do the things listed below. When it gets above 100 degrees Centigrade, bad things start to happen and can cause permanent damage.
Fortunately, there are programs such as CPUID HWMonitoryou can use to monitor the temperature of a laptop's CPU and GPU. A laptop doing light work such as email or browsing should run in the 50-70 degree range. One working hard may run in the 70-90 degree range. If it starts to run in the 90-100 range, do the following:
Get the best cooling pad you can afford. I use theCooler Master SF-17for running benchmarks and stress tests.
When gaming, select a high performance power plan and use the advanced settings to limit the maximum processor state to roughly65%. This won't slow you down because the limiting factor in game play is the GPU, not the CPU. Set it back to 100% when you're done.
Turn off wi-fi unless your game or application requires it.