Hello
Sad to here that you are having problems with the mediator, but looking at the card info,its a card with a moblie gfx chip and some of these cards don,t work at all or just show garbage on the screen. it Looks like the radeon is the problem.
Narrow it down take radeon out, try another pci card,ie ethernet card ie 8029 or sata sii3112,3114 that doesnt need dma,voodoo gfx card if you have one,if they work then its not the mediator,causing the problem.
I had the same problem and it was the radeon with mobile chip,it could also be that it needs the 5v hack to get it working,or just get one of the old saphire 9250 cards they normally work with out the voltage hack,was lucky to pick one up off ebay.Really cheap for 14 euros works a dream.
Good Luck
Regards Laurence