will run off of it. RAM affects how much memory can be placed into it before it dumps old memory off the edge. Lastly, a harddrive. If you are a hardcore music listener or movie watcher, a harddrive is important. A harddrive is you main computer memory where everything is stored. The average harddrive nowadays is about 500GB I think. Anyway,do research on each of these components of a computer before you buy and you will be golden Source(s): I look at a lot of things when buying. Things like hard drive and RAM don't bother me much, except in laptops where I don't like to tyr to modify them. In a desktop, I look at the motherboard, CPU (both speed and brand; I have a preference for AMD but I can live with Intel), graphics card, network card, and the case. I also like to check out the overall weight and dimensions of the finished desktop, to determine if it fits on my desk or if it needs to go on the floor. I can live with hardware not being so wonderful, because I know I can customise as soon as the warranty expires. With that being said, I rarely even consider buying pre-built desktops; building your own leaves a lot more room to customise. In laptops, looks aren't important; most laptops look pretty okay anyway. I take a good close look at the CPU, RAM and network card, and I'll always choose a laptop with a wireless card