Slow Computer

First thing I would say is keep in mind the limits of your hardware. 6GB of RAM is more than enough for most users but perhaps your CPU, OS or another factor might be the problem.

REINSTALL OS
Assuming you have noticed a slowdown over the 2 years the best thing you can do is a full re-install of your OS (and spend the next day installing updates and any programmes you want). This quite often isn’t practical or possible but it is the best thing you can do!

HARDWARE CHECK
Before doing anything I would check to make sure the hardware is running as per its specs. There is a free tool call CPU-Z that will let you know if the computer is reading all the memory as well as giving you specs on your CPU.

CLEANING
If all the hardware seems OK I would also consider opening up the side of the computer and cleaning it out with compressed air. Computers often get filled with dirt and dust which can cause the computer to throttle back so not to overheat. Running CPU-Z or another similar programme during a noticeable period of slowdown should give a clue to if this is happening.

UPDATE, UPDATE, UPDATE
Next I would make sure the OS, drivers and all software are fully up-to-date.

ANTI-VIRUS
Also check the settings of your anti-virus and make sure it is only updating and doing full system scans during your low time with the computer. It would be a good idea to run a virus scan now if one hasn’t been performed recently.

MALWARE SCAN
Download Malwarebytes and run a full scan. Delete any threats it has detected that you don’t want.

CCLEANER
Next step would be to download CCleaner and do the following 3 steps:

1. On the “Cleaner” page click “Analysis” and once it has scanned everything have a look at what it has found. If your are happy to proceed click “Clean”. If you know what your are doing you can tick/un-tick some of the options to give better control. This section of CCleaner will delete temporary internet files, system logs, cookies, etc. from your PC. Just remember that after running it you may be logged out / have to re-set preferences / re-prompted for passwords on websites.
   
2. On the “Registry” page do a scan and clean up your registry. It may prompt you to back-up the existing registry first, this is a good idea if you don’t know what u are doing. You may have to repeat the process several times to fully clean.
   
3. Finally on the “Tools” > “Startup” page you can see a list of programmes and services that launch at start-up. If you don’t require a service disable it but keep in mind that not all start-up services are bad (i.e. cloud storage syncing, anti-virus, etc.).

DEFRAGMENTATION
Defragging basically re-arranges where data is stored to improve readability. In Windows, right-click on your hard drive in My Computer, click Properties, go to the Tools tab and select “Defragment now… “. Here you can defrag the hard drive immediately or set it to do so on a schedule. Like your anti-virus you should set it to defrag at times where you do not require the computer performance.

ADDITIONAL INVESTAGATING
If this still doesn’t give you the improvements you want I would try to dig a bit deeper into the root cause of the problem. Running resource monitor or another similar application while using the computer can let you see where the bottle neck is.

FURTHER IMPROVMENTS
You should continue to do some, if not all, of these steps on a regular basis to keep the computer tuned up. There are also loads of tips online for how to increase PC performance such as turning off some OS features. A quick internet search will reveal all.

Windows needs around 3 gig free space,
otherwise it slows down.
Could be a virus taking up ram.
turn on pc, After 30 minutes,see task manager ,how much memory is free ,
is cpu at 90 per cent usage.