Will my old Geforce FX 5200 be better than my onboard Geforce 6150 SE?

Q: I bought my computer a couple years ago. It came with an onboard video (i think Geforce 6150 SE nforce 430) and i havent had too many problems playing online games. Somone was telling me that this was a really bad setup for an online game and i would get better performance even if i was useing my old videocard (i think it was from the geforce fx series… maybe 5200? its in a box of spare pc parts somwhere) I figured id ask somone who might have a clue.