zestou :
IF i have low ram, like 2gb of ram. what will that do? what is the difference between having 2gb of ram and 8gb? etc
If you have 2GB of RAM you probably have a very old system as well, as they haven't sold systems with that little ram for nearly a decade. Second to that, it is simple MATH, if you have only 2GB or RAM to run EVERYTHING (Windows, Drivers, Managing files, AntiVirus Protection, knowing what Wallpaper you have, where the icons are, how your toolbar is organized, etc.) then when you start running programs (Instant Messages, Streaming Radio, Games) needs some to run too. If there is NOT ENOUGH to go around, in the old days the computer would ERROR on the screen that not enough RAM and crash. Since XP, instead it makes a 'temp area' on your Hard Drive to write 'down' the information needed to run a program (think of it as a folder on your desk with a lot of notepad paper in there to keep writing down what your thinking every moment) then READ it back to WINDOWS to actual 'process'.
So.... if... you.. kept.. writing....each.. word.... you... are.. reading.. right...now... then having to.. read each.. word... out.. loud.. one.. at.. a .. time.. to 'read' what you wrote.. as you can see it adds alot of 'lag' or delay in making things work.
Lastly, programs like GAMES need at LEAST 4GB JUST to the GAME (No Windows, no files, no antivirus, nothing, just the game itself), so if you have only 2GB for EVERYTHING, is that enough? NO.
Don't stick yourself or try 'fixing up' some ancient PC, they are NOT cost effective, as a BRAND NEW PC at Walmart is only $249, slap in a $149 750Ti, and you can play games that look TERRIBLE, perform BAD, but they 'play', and is performing better then that old 2GB system your trying to patch up and much cheaper.
As I tell most people, if you can only spend 'a couple hundred' and want to Game? GET A CONSOLE. You can get ALOT better performance and visually looks GREAT (point of a VIDEO game right?) of all current titles out there without any worry about 'upgrades' patches viruses etc. If you WANT a PC to play games, you need to PAY TO PLAY, period, and the BASIC standard is at least $750 for a i5 CPU, 8GB RAM, 1TB HDD, with a AMD R9 or a Nvidia 660/670/760/770 (seen a few earlier sales of 970s as low as $300!) with a capable PSU (500-600W). PC side is technical, expensive, and demanding, there is no 'short cuts' if you want to play games on PCs