There is "really" no sure way of knowing if the drivers are/were installed.
On Intel chipset drivers, they "may" be listed in "Add/Remove Programs". If
you also have Intel Application Accelerator installed, then you should have
the chipset drivers install (required be I.A.A is allowed to install.)
On VIA chipset, there is supposed to be a Registry entry which lists out the
installed version of the drivers. For more details, see
www.viaarena.com.
As of nVidia, I can not state anything, since I never have used any nVidia
motherboard chipset.
As of most chipset drivers, you can/should always install the "latest"
released version for your chipset level. It seems that you can always
over-write the installed ones without much difficulties.