What adapter should I get?

To connect a ADC display to a DVI computer you need the DVI to ADC adapter (the expensive one),
<http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore.woa/wa/RSLID?mco=MT I1NzY&fnode=home/shop mac/macaccessories/displays&nplm=M8661LL/B>
not the ADC to DVI adapter
<http://www.smalldog.com/product/12651830>

The Apple adapter works fine. I have been using one for years, with two different computers. Most of the bad reviews are complaints about the price, or having to use the adapter in the first place. It is expensive because it has to include the power supply for the display. With the adapter, you can't turn on the computer with the display's power button.

I just purchased that setup and indeed it does work to use my 2004 display as a 2nd monitor with my 2007 iMac...

iMac --- mini DVI to DVI adapter ($20) --- DVI to ADC Adapter ($100) --- 17" Apple Studio Display LCD

But here's my question for next time: Obviously, the Apple ADC adapter is so expensive b/c it includes the power supply. But does it need it? If the ADC monitors worked pre-2004 by drawing their power from the computer, couldn't it draw it's power from my iMac?

Any experience with how this may affect/damage/work/not work would be greatly appreciated.

The computers that could drive ADC displays directly had power supplies with extra capacity (over 100 watts extra) to handle the display. They provided 24-28 Volts though extra pins on the motherboard, though a special tab in the graphics board, to the ADC pins. The newer computers don't have any power available at voltages needed for ADC displays so there is no place to connect for display power, even if you didn't mind overloading the power supply.

If you could find the right connectors, you could buy a power supply and build your own adapter, but it would be a lot of work for the money saved. There were a few non-Apple DVI to ADC adapters, but they cost even more than the Apple version. The Apple unit also include DVI signal amplifiers to drive the extra cable included in the adapter, but they would not be needed if you don't include much cable in the adapter.

With all the How To's online, I can't believe NO ONE has mapped out the different pins on the ADC. Who cares about the usb and whatever, all i want is to use the monitor. There must be a simple way to change it to dvi and stick a separate power supply.

Here are the connector pinouts:
<http://pinouts.ru/Video/apple adcpinout.shtml>
<http://pinouts.ru/Video/dvi_pinout.shtml>
You will also need a DC power supply, 24-28 volts, up to 5 amps, depending on the display.
It may not be easy to find the connectors (especially ADC), but you could just cut off the cable at the ADC, and splice on a piece of a DVI cable.

Wow thanks for the diagrams.

My main problem is, how would you be able to cut off the adc and still know which wires are which?

Cut just one wire at a time and use a multi-meter or continuity tester to measure from each pin to the wire.

That makes perfect sense. I'll try it! Thanks!