[zeekgenateer]

OK motherboards is one of the main components of the computer. It connects all the hardware together (CPU, GFX card, USB, DVD drive, Hard Drive etc) so the computer can use it. Motherboards support many differnt things, but motherboards do not work with opposite CPUs (a motherboard made with an AMD CPU in mind, will not work with an Intel CPU). Motherboards also can have different types of RAM, DDR (which is the normal slow stuff) and DDR2 (which is much faster). These types of RAM also have different speeds within their categories. I usually use the MHz speed, but many prefer the PC speed rating which is just a different number with the same meaning 667 MHz = 5400 PC. Your motherboard will work with slower and faster RAM, but not at its full potential. It is best to get the same speed RAM as your motherboard.

And with motherboards definitely go get a new one if your old one came with the computer you bought. Proprietary (what geeks call Dells, Macs, HPs etc) computers sometimes don't like hardware not made by their companies.

Your RAM speed is determined by your motherboard. You want a motherboard with DDR2 capability and and a speed of at least 667 MHz (equivalent to PC5400). So if your motherboard works wit 800 MHz RAM get 800 MHz RAM.

Concerning Processor Intel Core 2 Duo is a type of processor (processors are also called CPUs and are used interchangeably). Depending on how much you want to spend get the fastest for your money, but make sure it is compatible with your motherboard (AMD processor motherboards do not work with Intel CPUs).