The cards you are talking about would be OEM parts that they supply to HP etc for ready made systems, quite low end.
What type of use do you want from a new card and if gaming is involved what type and please include your screen size ?
You wont get anything fantastic without a PSU upgrade but im sure we can get you a nice performance boost.
For referance the card you had/have is roughly the same as Nvidia's old 9500GT from what i have read about it.
Also can you give us a budget to aim at and we can send some links to suitable cards