i'd assume that computers like DELL have DDR and my Hp has a DIMM but its a laptop so i don't know how it would differ.
You can use a software called CPU-Z to see the exact modules you have running in your system. It also lists the speeds at which they are running at.
Also, a general rule to follow is that if it is a computer, like a desktop, you are using a form of DDR memory. DDR comes in three forms: DDR1, DDR2, and DDR3. The only difference between these form sis the speed at which they run on.
If you use a laptop, then they use RAM sticks on the SO-DIMM form.
Hope this helped you out. :)userpassword to open computer
Smart answer! I know that Aleksandr is the man :-PType blinker