Please excuse the late response.
Most of the Voodoo 2 cards with this behaviour that I have had for repair have had a thermal problem.
Considering the age of the cards, it is quite possible that one of the chips is thermally sensitive and will malfunction above a certain temperature. You can check this by trying other Glide applications such as Donut Demo or UT Intro, Q3 Demo etc...
If it behaves the same, it is probably the temperature.
You could also check the card mechanically by bending it slightly in different directions during operation. It should not lock up in the process.
My suspicion:
CK FBI
Gendac (most likely)
Bus Switch (possibly)
- Backfire -
Repair of 3dfx Devices and Soundcards with passion...
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