That particular OS is already installed dual-boot on that machine, but it wasn't even necessary to resort to that
The motherboard is a Microstar MSI
MS-6156ZX.. But it wasn't on the list of Geforce/motherboard compatibility. And the MSI boards which were listed, were listed under "Motherboards successfully tested"
And btw, the acceleration seems to work very well on a certain something-98 OS
Why it wont work in Linux is still beyond me.
I still have the strong feeling that it's the motherboard which doesn't like the Linux nVidia driver.