Dimness/Fuzziness after moving monitor to other PC...

Right... so I bought a new VX922 for myself.. because... hey, I wanted to move to flatscreen... and I figured I'd give my mom my old Hitachi 19", replacing her old old old Gateway 17".

On my computer, it had pretty good brightness, good response, decent colors, etc....

I move it to hers... its fuzzy, its dimmer, and the colors aren't as good... Now trust me, everything is still readable... its BEARABLE... but its just lower quality all of a sudden... and for my mom who's eyes are aging already... this is not good.

Now, the stats that make a difference between them I'm going to list, and maybe I can get some ideas here as to why this would happen?

My Computer (Homebuilt):
GFX: Nvidia GeFore 6800 GT
Power Supply: 450W Antec TruePower (came with the case, 5 years old)
RGB connection.

Mom's Computer (E-Machines):
GFX: nForce2 Integrated GFX
Power Supply: Some Cheapy 300W
RGB Connection.

So... There you have it. I even moved things to be the same Resolution and Color (1024x1280, 32 Bit)... And still the same problem with it being dimmer and more fuzzy.

If you need anymore details, please ask...

Any help would be appreciated, thanks!.