Article: If you leave your computer on all the time, you can often fix a problem by turning off the computer, then unplugging it (or remove the battery, if it is a laptop), then holding down the power button for 30 seconds while computer remains unplugged (this will often cause a light, or lights, to flash), then reinserting the battery, plugging the computer back in and powering it on.  By cutting off the power to the motherboard, it allows the hardware to reset and the memory to clear. You will need to take a look inside for this. Remember that any time you need to open up your computer cabinet, shut down your computer and unplug it. If you have long hair, tie it back. Take off any jewelry that might get in the way. Also avoid wearing any clothing that produces a lot of static, as a spark can damage hardware and cause intermittent, hard-to-troubleshoot problems. Many computers now come with built-in diagnostics which can tell you if you have certain issues. 4 brands of computers that normally have diagnostic options are HP/Compaq, Dell, Lenovo and Acer. To access these diagnostic options:  Power down the computer, wait a few seconds then turn it back on. HP - Immediately start pressing F2 on startup to access the diagnostic menu. Select Start Up Test, Quick, One Pass (if option is present) to begin the testing process. Dell - Immediately start pressing F12 on startup to access the diagnostic menu. Use the arrow keys to select Diagnostics from the menu. Lenovo -  press F10 during the boot sequence and this will launch the Lenovo diagnostics. Acer -  restart the computer and press the "F2" key during startup. Once the setup utility comes up, go to the diagnostic menu and run a test. Write down any error codes and consult the internet, the computer manufacturer or a local technician for assistance. If it’s hot, then there may be a heat related issue. For laptops, you generally do not want to try to open the case, but you can still vacuum the fan ports. Some computers just run hot, particularly laptops, but heat is never good for electronics. Gently examine the front and rear fans and blow out any dust. You can apply a clean cloth to dust out hidden particles. Remember: Your computer must be shut down while you're cleaning inside it.  If you have more than one hard drive in your computer, avoid installing them right next to each other in the chassis; this makes them more prone to heat failure. To install an extra hard drive in a wide slot, such as the slot that holds your CD-ROM or DVD-ROM drive, you can buy mounting brackets at a store that sells computer parts. Even if your computer isn't having problems, it's a good idea to clean the fans regularly. Before you close up the case, check all the cables and make sure everything is still plugged in. If you have to reset a video card or a stick of memory, avoid applying heavy pressure to the motherboard as this can damage it. Many times when doing a Windows Update, your system may download and install an incorrect driver, which may result in the computer freezing. You can check the status of drivers from Device Manager. Any devices with a yellow exclamation next to them are in an error state. Unplug any USB devices, if connected, and see if the error goes away. If so, that device is a problem. Power-on your computer and see if it works. If it does, good; otherwise you can restore your computer to an earlier configuration. System Restore will roll your system back to an earlier set of drivers. It can be accessed by pressing and holding the Windows Logo key and pressing R, and then typing "rstrui" in the Run dialog box. Using a restore point to restore your computer can remove software (like an app, driver, or update) that might be causing the problem.  Once started, System Restore can NOT be interrupted, so be patient. Changes made to your PC by System Restore cannot be undone if you are running it in Safe Mode or the Windows Recovery Environment. Your hard disk is a storehouse of information, so when it gets used for a long duration it might get cluttered and patchy; this slows down the performance of your computer. Hence, use your Windows utility CHKDSK to scan and remove bad sectors on regular basis. It is the best preventive way of maintaining computer health.  If all else fails, reinstalling your operating system might help. Back up your files before doing this step.

What is a summary?
Give your computer a bit of rest. Determine if your computer is overheating. Run a diagnostic check. Open the cabinet of your computer and check the temperature of the metal chassis. Inspect your device drivers. Try a System Restore. Inspect your hard disk. Install and run a good antivirus and anti-malware program. Reinstall your operating system.