If your PC is suffering from following problems

1. Your Wi-Fi network is now dog-slow.
2. Your display looks terrible.
3. Your printer is spewing out garbage.
4. Your default printer is no longer the default.
5. You see daily, consistent error messages citing memory problems.
6. Your PC starts up too slowly.
7. Videos play sans audio or image
8. You broke a key off your keyboard.
9. You bent a pin on one of your PC’s ports or cables.
10. Folders show only large icons

Then read this article : 10 Fast Fixes for Nagging PC Problems