Quick RAM question

[\=hitman=/]

Ok, well I've been wanting to buy some more RAM for my computer. Well I understand that I have to buy the same RAM type my computer uses right now. How do I figure out what type of RAM my computer uses. Here's my system specs:

Dell Dimension DIM5100C
Intel(R)
Pentium(R) 4CPU 3.00GHz
504MB RAM

Would this RAM be compatible with my computer:

http://www.tigerdirect.com/applicat...p?EdpNo=1071038&Sku=ULT31690#productresources

 

[LinkedKube]

go to control panel, computer information on the left column, see how much ram you have currently, passed that we would have to know what mobo is in your system

 

[\=hitman=/]

Is the RAM product I posted compatible though? And how do I figure out what mobo is in my system?