Follow these steps and you will have much faster and more reliable PC:
Disable Startup Programs: If your PC taking long time to Starting up, then you have many programs starting up when your computer starts. 
To fix this, Disable UnNeccessary Programs from Windows Startup
In Windows XP/Windows 7/Windows 8
Press “Windows + R” Button to Open Run Dialogue Box, Type “msconfig” there and Press Enter
In Windows 10 
Right-click on the Task Manager and click Task Manager(or Press Control+Alt+Enter Button Together to Open Task Manager), Click the Startup tab and you will see there list of programs that start up with your computer. If you see program that dont need to be there, right-click it and click Disable, Then Restart your Pc, will be See Your Pc will Take Less Time to Start

No Special Effects and Animations: Windows Animations and Special Effects also Effects Windows Speed, you can Disable it to Speed Up Your Pc

To Do That, Right-Click on Start button and click System.

Speed Up Windows Perfomance

It Will Open System Properties Menu, Then Click Advanced tab , Then Under Performance Click Settings.

This will open the Performance Options menu. In the Visual Effects tab, Speed Up Windows Perfomance

We Suggest to choose Adjust for best performance to turn off all unnecessary animations and special effects, or you can select Custom and de-select the visual effects you think can live without. When finished, click OK to apply your changes/settings.

3.Run Disk Cleanup: It Will improve performance and free up space on your hard drive. Disk Cleanup help clean out the temporary files, installers and other junk littering your hard drive. To do this, search Disk Cleanup in star menu, run it and click button labeled Clean up system files. 

Speed Up Windows Perfomance
Power Plan: Make sure you are not using Power saver plan if you don’t need to. Even desktops will sometimes Use a power-saver option, which does not do you any good unless you are trying to conserve battery life. Open the Control Panel and go to Power Options to see which power plan you are currently using. 
For better performance, make sure you using High Performance or Balanced plan (or plan from the PC manufacturer that says it’s balanced).
Speed Up Windows Perfomance