Personaly i think it could be a aca problem,since i am trying a mediator bought from amibay ,and the seller bought some crazy update chips ,actually 3 of them ,tah elbox don´t even heard of,they say upgrade is made only by 2 chips,so i replace the original ones,and had some problems.
First my mediator system don´t boot with aca stays black from the beginig.
2 won´t boot because of a burned or bad S3 pci uv64
Then i removed the aca,and inserted a blizzard 1230 changing the jumper on the board and booted fine.
Now i am going to install the mm cd becaus i don´t get native pc resolutions on the resolution manager under the os 3.9.
So it could be an aca but or config jumper,since my board has a jumper but i didn´t change that one.
Thanks in advance