Is it possible for certain computer parts to not work there?

My friend wants to build a computer and he wants to know if certain parts won't work together, is there a possibility of like a mobo not working with the RAM, or any combo. of that sort?

There are different "types" of just about everything...

you could get an AGP video card and it won't work on a motherboard with only PCI slots (although those are rare now).

Your motherboard may only support SDRAM, not DDR-SDRAM. Plus there are 15 other types of ram, too...RAM from your old P-100 will not work in your P4-2.4Ghz machine...

Same things goes for processors...different processors have different configurations/"plugs" if you will...that go with specific motherboards. You could have Slot-1, 478, 423, Socket A, etc...and a 478 Processor won't fit in a Socket A slot (besides the fact that 478 is Intel and A is AMD)

Are you looking for this broad of a description? Cuz motherboards are specific to the processor, too..

Rather than spend the rest of eternity trying to figure out what goes with what, decide what your budget is and what you want to do with the computer. Then decide if you want to go with an Intel or AMD processor. AMD is cheaper at the lower end while maintaining good performance. Intel has the better value at the higher end (the P4 2.8C is a great deal right now), and of course the performance is gonna be spectacular. :D

When you've decided on a processor you can pick a motherboard. All your other hardware choices will be based on that, since they all plug into it. ;)

One tip: Don't skrimp on the motherboard. It's arguably the most important purchase in a new system, and will determine your ability to upgrade in the future.