This was the game that caused me to get my first PC with Voodoo2. I was on a Mac up until that point. Saw it at a friends house and could not believe what I was seeing. A few weeks later I had my first Gateway PC, I believe it came in a box with cow spots. I don't even know how I got my parents to buy it for me, it must have been a small fortune at the time.
I don't think the gap between consoles and PC was ever wider. I didn't even know anything like this game was even possible until I saw it. If I remember correctly, Doom II did not require this kind of hardware acceleration, but this game did.
Why do I remember Jonathan Frakes being Kyle Katarn for some reason? Great game.