Did you already try the latest firmware?
Additional information incl. all user manuals: MNT ZZ9000 Amiga Graphics Accelerator + Network, USB — MNT Research
ZZ9000 revisions R-1 and R-2 need an important hardware fix. Check this easy guide for cutting the trace:
The ZZ9000 compendium by Greg Donner: ZZ9000 Compendium: Preface
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