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As a rule, you want to keep at least 15% of the hard disk space free to keep the computer running smoothly. Use the following steps to check your hard disk space:  Open File Explorer. It has an icon that resembles a folder with a blue clip. You can find it in the taskbar or the Windows Start menu. Click This Computer.  Check the disk drive space. All disk drives are listed below "Drives and devices." There is a bar graph next to each disk drive that shows how much space is being used. you do not use. Right-click an app in the Windows Start menu and click Uninstall. This opens the "Programs and Features" window in the Control Panel. Click a program and click Uninstall above the list of programs to uninstall the program. Don't forget to empty your recycling bin. . Some programs may start as soon as you turn on your computer, running in the background so they will load quickly when you open them. Use the following steps to disable startup programs:  Right-click the taskbar at the bottom of the screen. Click Task Manager  Click More Details at the bottom of the Task Manager. Click the Startup tab at the top of the screen. Click an app. Click Disable in the lower-right corner. This option is not available on all versions of Windows. Using High-Performance mode on a laptop will drain your battery quicker. Use the following steps to switch to High-Performance mode  Right-click the Windows Start menu. Click Power Options. Click Additional Power Settings in the menu bar to the right. Click Create Power Plan in the menu bar to the left. Check High Performance  Click Next. The fewer bugs, viruses, and bits of adware your computer has to manage, the more time it will have to devote to other processes. Not only will this keep Windows itself running smoothly, but some viruses ride in on Windows updates that are downloaded long after the update is available (and therefore are not monitored as closely). This can clean up hundreds of megabytes by deleting temporary files, unnecessary system files, and emptying your recycling bin. Use the following steps to run Disk Cleanup:  Click the Windows Start menu. Type Disk Cleanup and click the Disk Cleanup icon. Select a drive. Click Ok  Check the file types you want to clean and click Ok. When data is fragmented, your computer must search for the fragments of files that could be spread all over your hard drive. Defragmenting will organize your data and free up space so your computer can access data faster. Windows 7, 8, and 10 defrag your hard drive automatically. If you are using any older version of Windows you may need to defrag your hard drive. You can use the following steps to defrag your hard drive on Windows 10: Use the following steps to run Disk Defragment:  Click the Windows Start menu. Type Defragment and click Defragment and Optimize Drives. Select a drive. Click Optimize. There are 20 visual effects you can turn off or on. Use the following steps to turn off all effects and maximize performance:  Click the Windows Start menu. Type Control Panel and click Control Panel  Click System & Security  Click System, Click Advanced System Settings. Select the bullet which says "Adjust for best performance". Solid State Drives are hard drives that have no moving parts. They are much quieter and quicker. Purchase the right sized Solid State Drive for your computer and install it. . Most computers come with 8 GB of RAM, but you can add more if you use it to run many applications. The extra RAM gives your computer more memory to perform tasks with, which will make your computer faster. In order to install RAM on your computer, you'll need to see what type of RAM your computer takes and purchase it. You'll then need to open your computer and install it.   To see if you need more RAM, initialize the Windows Task Manager by pressing "Ctrl + Alt + Del" and click Task Manager. Under the Performance tab, find the area devoted to Physical Memory (MB). If the number next to "Available" is less than 25% of the Total MB, you may need to add RAM.  Adding more memory may not necessarily make your computer run faster. If your computer is slow to switch between windows or tasks, or if you often have many browser tabs open at once, additional RAM may help.  You can take your computer to an expert to add RAM, like the Geek Squad at Best Buy, or you may decide to add more RAM yourself. Just be sure to do your research before attempting to do it on your own. Your computer generates a lot of temporary files each time you boot up and/or use applications. This takes up a considerable amount of space, further slowing down your system. You should clean it whenever you think your PC is slowing down more than usual. To do this, press "Win + R" and then type %temp%. Permanently delete all the files present in the folder. Just skip the files that the system says it was unable to delete. It could be that your computer is running slow because of the old hardware that is running the newer software. When a computer was released the hardware was designed to run a specific OS or software versions. When newer versions of the software were released it was supported by the older hardware. The reason your computer may be running slow or freezing is because the older hardware is struggling to keep up with the newer software. Try replacing the processor to speed up your computer.

Summary:
Check your hard disk space. Remove any programs Prevent unnecessary programs from starting when the computer boots up Change the power plan of your desktop computer to High-Performance mode. Install an anti-virus program, spyware scanner, and an anti-malware. Keep Windows up-to-date. Run a Disk Cleanup. Run a Disk Defragment. Disable visual effects. Consider switching to a Solid State Drive. Add RAM to your computer Clear temporary files on your computer. Consider upgrading your computer's hardware.