"The best driver software for your device is already installed"

[Guest Atticus]

I have an 8400M GT on a Sony VAIO laptop.

I keep trying the have disk method with the modified IFO for the last two Windows Vista 32-bit drivers (17493 and 17512) yet everytime I select the folder with my drivers and hit next, it tells me that I already have the latest drivers, which is nonsense.

The driver I currently have is: 7.15.11.117

and it's over a year old (4/20/07).

Is something wrong? do I need to uninstall the drivers first?

[Dox]

uninstall your current driver first then attempt a new install of your chosen driver