Can’t Read DVD’s Burn From Other Machine

Hi guys!
I currently bought a new surplus system for my sister. It is a Pentium 4 3.2, 80gb.
1.25Gb, fx5500 and used my previous DVD Writer (Samsung writemaster) from my other rig that is an AMD Phenom II x2 550 BE, 4gb, 780G, 4670.
And the problem is.
It can't read my DVD's burn from my AMD rig. What could be the cause?
Is it my Processor?
Or my Motherboard?
