Troubleshoot Slow Computer

Slow computers are always a problem for home users and professionals. This document does not cover slow boot-up, slow Internet or slow network. And also intended for Microsoft users.

Reboot

The first universal pc troubleshooting step is to restart your computer. If any unwanted applications running or any file corrupted or any one time problem situations or issues may will get solved - if you are lucky.

Background Programs

One of the most common reason is background processes. You can check running processes by opening Task Manager or RESMON. Uninstall any unwanted programs installed on your computer with or without your awareness. Disable unwanted startup programs. You can check start up programs by opening MSCONFIG.
Note: If you installed anti-virus on your pc then verify that anti-virus is not running scans on background. It might considerably slowdown your system.

Temp Files

Temporary files are accumulated as program runs but they never deletes as those programs exits. We can use third party cleaner softwares like CCleaner or Disk Cleanup. But a manual deletion of temp files is recommended. You can delete all files in %temp% directory (type %temp% in run prompt and press OK to open temp folder). If any files are not able to delete, you can skip it.

Hard Disk Free Space

You must save some space on system drive to allocate page file or virtual memory and to create temp files. If you have insufficient space that will make your pc slow. It is not necessary to allocate page files on system drive. Please verify those settings on
System Properties/Advanced/Performance/Settings/Advanced/Virtual Memory

Bad Hard Disk

Run tools like ScanDisk, chkdsk or any third party tools to verify that the hard disk is physically ok - dont have any bad sector problems.
Run Defrag to to order files in the hard disk

Malware

Spyware and Malware are the primary reason for slow computer other than physical issues. All anti-virus softwares are not good in detecting malware  softwares. It is recommended to scan with a specialist anti-malware tool. Free version of Malwarebytes is a good option.

Virus

Yes dont forget to scan for viruses too, even if you enabled live protection.

Hardware Conflicts

Cross check any hardware conflicts using Device Manager. Check for any new unrecognized or uninstalled or malfunctioning device. Install or update with proper device drivers. Remove or disable any faulty devices. Try to remove physically or disable in BIOS.

Windows Updates

Try to update windows with latest updates. Sometimes these updates may slowdown your system. so disable automatic updates. and uninstall last updates.

Driver Software

Update driver software or Rollback last driver update according to the problem occurrence- if problem started after driver update then rollback otherwise update.

Memory Upgrade

If you are using your computer for more than two years then it is recommended to upgrade your RAM. Day by day large applications are introduced in the market. Your old computer may not have the required amount of RAM to handle the application.

Hard Disk

Hard Disk is one of the slower things on a computer. If you can afford a little cost then you can upgrade to Solid State Drive(SSD).

Registry

If you are such a person who likes to try new applications (mostly students) then there is a chance to have a bad registry(orphan links). You can use third party tools to clean the registry.

Processor Heat

 Dust, dirt and hair can also constrict proper airflow inside your computer which can cause a computer to over heat. Make your computer cabinet is clean and fans are not obstructed.

Reinstall OS

Reinstalling the operating system can increase performance by getting rid of old software or drivers that may be on the computer and causing the computer to be slow.

Hardware Issues

Finally if your computer is still slow after trying all of the above recommendations there may have a more serious hardware related issue, such as failing component in the computer like Hard Disk, CPU, RAM, Motherboard, Add on Cards. You can run hardware diagnostic tools like Ultimate Boot CD(UBCD). This utility provides many diagnostic tests to find the BAD piece of Hardware.