Where to start for a slowing running, unstable computer?

I recently reformatted my harddrive (300Gb) and reinstalled Windows XP Pro edition. I've carried out all updates and installed Norton Antivirus as well as other games and programs.

Since then, my computer can be quite slow running causing programs to stop respondnig for several minutes and sometimes crash completely. It has a 1.8GHz processor which I know isn't the fastest around but should give a good turn of speed.

I have been into MSConfig and disabled various start up programs. There is nothing in my start up folder.

Can anyone suggest where to go or what to do next? Many thanks.

Where to start for a slowing running, unstable computer?computer virus

The easiest difference-making upgrade is to install more RAM. Visit www.crucial.com, have it scan your system, and see what your options are for installing more RAM. Good luck!

Where to start for a slowing running, unstable computer?free spyware remover

Is there a lot of junk running in the background? Windows media center had all this extra garbage that was slowing it down.
You need more ram.
If you have anything on your computer from AOL - get rid of it. I have found that to be a problem in many computers I have fixed.

Get more RAM. You should have at least 512, but a gig would be better.
I go here when I need help: http://www.pcpitstop.com/

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