I believe I saw your post in another forum. I took the liberty of trying to research your problem. Take a look at this review. Check the part about "upgradeability" and see if it answers your question.
Im not very good with computers. I know my way around em, but i dont know in depth things. i cant run multiple games i have bought, so i checked the requirements and i bought a radeon 9200 (it had morphing and lighting, that was what i needed)
i have a gateway 500s with windows XP and intel 828456g/gl integrated graphics. now, i believe you cannot disable it at the mother board, if there is a way, please correct me. i have installed the ati card and my system is reading it, but when i install the driver, there is an error. my guess is that the intel integrated is trying to block it. i have tried removing the driver in control panel and in the device manager in both normal and safe mode but it seems that it has popped back up and is preventing my ati card from being used... can anyone PLEASE help me?