Basic speaker problem

[mikb]

My mum bought new speakers for her pc. They don't work with her pc, but they do work with mine. Also, headphones plugged into my mums pc work, any ideas how to make the new speakers work?

 

[Law]

What's your mom computer spec, sound card wise and what's the speaker's spec.

 

[Crysalis]

Are you plugging them into the right jacks?

Headphone/Line Out jack is NOT speaker jack