1999 "the area 51" help

#1
Attached is a advert for a 1999 "the area 51"
I was 13 at the time and wanted one so badly I begged my parents to buy one as our next family PC. I didnt get one!

Now I have the means to build one. As you can see from the advert the system had both the Voodoo 3 and a Nvidia Riva TNT2 in one system and would "switch" between the two via a toggle switch.

I would like to know how this worked or if anyone has one they can send me pictures of.

Looking forward to recreating a classic Alienware rig.

Thanks for any help received. 1996.jpg