[X4U] Difference between vid cards

[Crandon David]

In my G4 Dual 500 with 1 gig RAM, I have an nVIDIA GeForce4 MX video  
card with 64 MB vRam in an AGP slot. Running the latest 10.4 software

Streaming video's from the net are often choppy. Very annoying.

My cousin has a used white iBook, 1.2GHz, 1 gigRAM with a ATI  
Mobiltiy Radeon 9200 4x AGP with 32MB vRam.

I know this card is a later edition than my card, but less video RAM...

Will I have better luck with video's being non-choppy? If not, how  
easy and cheap is it to upgrade the card? If that is indeed the problem?

David