Strange problems with Radeon 7500 (multi headed)

We have 3 of these cards setup in a CPU here, and can get Photon to work
well with it, but we’ve seen some very odd behaviour:

  1. If we restart the CPU, which automatically restarts Photon and our
    application, the CPU will hang just as Photon start. If we kill the network
    drivers just before starting Photon, then Photon starts up properly; we can
    then restart the LAN drivers.

  2. If we start Photon before our LAN card have finished negotiating with the
    switch, (i.e. we are alone on the LAN), Photon and our application will
    start properly. Our application only start AFTER at least one LAN cards is
    communicating with node 1.

Anybody have a clue as to what could be causing this? We’ve tried different
CPU and have seen the same odd behaviour in each case. We’ve also seen this
same behaviour using Rage128 cards, although with the Rage128, a dual headed
display has a much better chance of starting up properly.