On your computer, go to
system and maintenance
it will tell you how much memory (RAM) you have on your computer.
I have 4 on my laptop, but had 6 on the desktop that I gave to grandson for games.
It takes about 2 gig ram just to run windows, so if you don't have more than that, you have nothing left to run other programs after you boot up to windows.
You can take it to Best Buy and they will install if for you right there if you don't have anyone else to do it for you.
It is a simple pull out the chip and push the new ones in. If nothing is wrong with your computer, it will do all the necessary work itself of picking up the new memory chips.
If this is not your problem, sorry, but that sure is what it sounds like.
Best Buy employs intelligent "kids" who are taught to push sales, so don't let them sell you anything else.
If the repair is half or nearly half the cost of a new computer, you're better off going with a new computer. Computers are cheaper than they have "ever" been, but unless you know you're getting a deal, I'd wait until after Christmas to buy a new computer. Wait for the sales.
My son just bought a new quad core but I am still using very nicely a dual core, but next one I buy will be a quad core. It is faster.
Just wait for the sales.
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