The driver was written for Voodoo 3. The only way to get it working properly with later voodoos would be to have an update for the driver. I'm afraid that is not going to happen.
I doubt the overclocking helps much, really. Other components of the system are slowing the thing down, and the braindead Warp3D is not helping.
Proper voodoo4/5 driver is available for classic amigas thru
MorphOS (but this requires GRex).
