I have a G5 powermac with a 6800 graphics card - the one that comes with 2 DVI outputs and not an ADC one - I bought 2 apple monitors on ebay - the ones that are transparent (Apple Studio Display Model M7768) but even though I have the DVI to ADC adapter which plugs into the mains, I get no picture on the screen at all. I can switch the computer on and off and to standby using the on off button on the display but the screen remains black. I don't think the computer is at fault because I tried a friends flat screen with it and it worked fine. I need to know if I am the unluckiest ebayer who has been ripped off TWICE by different people selling the identical display or are they just not compatable with the G5 with the best video card. Can anyone out there give me advice - especially anyone who has used this combination?