3DLabs Permedia 2

There is a Windows 95 registry value that will increase 3D performance
for the FireGL 1K PRO while reducing the fill rate of the card.

HKEY_LOCAL_MACHINE/SOFTWARE/Diamond/DirectX/Direct3D.HAL.NoDMA "0"

You can also try to add these values:
SystemClock_8MB or SystemClock_4MB depending on your card to:
HKEY_LOCAL_MACHINE/SOFTWARE/Diamond/Display/
Then modify the value to at least a decimal value of 83 so the chip runs
at the proper speed.