Put more than 4GB of memory in your computer, or don't have over 40 or 50 open at the same time. :)

I built my computer about 12 years ago. I think I put 8GB of memory in it, the fastest processor available at the time, and a good graphics card. I can copy files, play music, work on a book, and have 80 or more browser tabs and windows open at the same time before my computer starts to slow a bit. I close everything and turn off the computer about once every month or two. Otherwise, it stays on 24/7. It's a tank. And it gets the job done.