You could do it the hard way; open the computer case and try to find the identification on the mobo, hoping it is in an easily visible spot.
If this fails or is too difficult, you could contact the manufacturer of your system and ask them.
In my opinion, however, the best way by far is to use software; download the free Belarc Advisor and run it. It will give you all sorts of useful information about your system, both hardware and software.
Hope this helps
Frank
is there any way to know what kind of mobo do i have without using any software? i have a AMD Athlon XP2200+ 1.8 GHz processor. my pc is a compaq presario S3100 nx. thanks for your help.

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