Okay. Starting over, Strip the A4000 so you just have a Bare A4000 motherboard in your case. Be sure the Mediators Edge connector is clean using some electrical cleaner. Seat it in & out of the 4000's Daughter card Slot a few times & re-clean. Be sure when you leave it in for the last time that it is fully seated. You should also do the same to the Mediators Bridgeboard (Zorro to PCI board) & try again with just the PCI NIC in the fist slot above the Mediator Bridgeboard & the Voodoo above it by a clear PCI slot or 2. This will allow better airflow for the Voodoo as she is a hot card. You MUST have the Voodoo in place with Drivers before using the NIC, as the NIC utilises some of the Voodoos 64Mb ram as a DMA buffer. Based on this fact, install the Voodoo Drivers first & be sure you have the latest 3.10 Elbox Drivers for this.
At this point, we are talking a fresh install again, but please persist. If you still appear to be dead in the water, use Medication to see if your Miggy is talking to any of your PCI cards.
One thing concerning me is you using a Plastic case! I wonder of you should be running a Ground wire from one the 4000's motherboard mount screws & one of the Mediators mount screws back to the Towers PSU case? I really am not sure about this, but I know grounds have to be used when using an ATX PSU in an A3000 due to the way the Miggy times itself through the Power On Button.
I know my A4KT was a b1tch to get up & running with the Mediator but persistance prevailed. This link might be of some help to you & it`s definately worth a read.
http://www.stom.co.uk/amiga-mediator/content/tutorials/guides/index.shtmlIf all is good eventually, I bet you a bottle of Jack Daniels your Miggy will lock up as soon as you try to go online with the Budda Installed. Mine did & was sold on very quickly as I am a SCSI guy when it comes to Miggys. It has something to do with the Fudge Elbox did RE DMA & I never found a solution. I really wanted the Faster & more versatile Floppy access from that card, but "hey ho" as they say!
Best of luck with this Kiddo. I hope things work out for ya!
Cheers,
Kin :-)
*edit*
Have you tried using just the Budda in one of the Mediators Zorros without any PCI cards installed?? Again tho, cleaning the edge connectors may fix this & those earth wires back to a screw on the PSU wont hurt to try. ;-)