computer slowed right down

I replaced the ram on my Acer computer from 2 256 sticks to to 512 sticks. It sped it up pretty good. That was about 6 months ago. Now it is getting slower than before. When i click on a website page it takes forever to change over. I also noticed that when i click on my foavorites, the pointer stops while scrolling across the favorites sites, just like i lost control of it than it catches up. When i click it seems like the screen does a double take than changes to the new screen. Does this sound like a virus or my ram is not working properly? My old T23 IBM laptop works faster, and it is on the same modem via a wireless adapter.

Have you tried clearing your cache (temporary internet files)? A large cache will slow down your web browsing -- in some cases, pretty significantly.

You might also go to your computer proporties and see if all the ram is still showing up. It could of gotten loose from moving your laptop around or possibly died.

Yes i cleared out the cache, it is a desktop, I will check out properties.

I cleared cache, ran a Norton scan, cleared some cookies out, no major threats it said. Now when I open explorer it will open 2 or 3 more sessions of explorer. It is like the mouse button is sticking on. I changed mouse and it did not help. It almost seems like there is a bug in there somewhere. What else can i check? When i open outlook express, it will open 2 or 3 sessions also.

Now when i got home i started the computer up and there is a small window on bottom of screen that say's LxrAutorun, i clik on it but it won't open, and when i run task manager it does not show up as an application. What is this and is it dangerous?

It's part of a Lexar thumb drive

http://www.file.net/process/lxrautorun.exe.html