I specifically chose an active DisplayPort <-> DVI adapter for use with EyeFinity right out of my graphic card vendor's list of confirmed compatible adapters.

Yet the screen fails horribly, it blinks on and off constantly, sometimes the graphics go screwy and the appropriate resolutions won't be available. Sometimes the resolution will be available but I'll discover it's only with interlaced refresh rates and bounces up and down. I have to switch the resolution back and forth, again and again, to get it to work correctly, and then it fails again and the process must be repeated the moment the monitor is turned off or I reboot. It's maddening.

What is wrong? Is my GFX card supplying insufficient voltage? (Firmware tweaks allegedly help some people, but my card's isn't modifiable.) Could the adapter be defective? Is it not "active" enough for my card and I need an expensive powered adapter? Is this endemic to DisplayPort in general?