System specs:
Motherboard: Aopen AX59pro
Processor: AMD K6-II 500MHz
Graphics: Voodoo5 5500 AGP

Fresh Install of Windows XP, with nothing else installed except SFFT 47 drivers, and Quake 2. With Glide, my FPS averages out at 20-23 FPS, which is a little below playable for me. What's up? I thought that my PC should be able to handle this easy, it's well above the minimum spec.

Are my expectations too high, do I need to install something, or is my hardware damaged?

The CPU is the bottleneck (very slow FPU). The game is very CPU-limited and a Voodoo5 can profit of more than 1 GHz in lower resolutions than 1280x1024x16. Try overclocking the K6-II.

Greetings from Germany,
Raff

Win9x and a K6-3 would be a better choice.