Dell U2410 does not enter low power mode with Mac Pro energy saver

There have been a few smatterings around about this issue, but no resolution as yet. I got a Dell U2410 LCD and it's connected to my Dual 2.66 Core Duo Mac Pro with an nVidia GeForce 7300GT.

If the computer goes to sleep, the monitor will correctly enter power save mode. However, if the display is put to sleep (through Energy Saver), it says "Entering Power Save Mode" then powers down and powers back on again immediately and repeats this cycle endlessly.

Other monitors connected to the computer have not had this problem, and it powers down properly when connected to certain Macs as well, and all PCs as far as I can tell. So it seems to be an issue of a power trickle out the DVI and ADC ports (same behavior when connected to either and connected to either DVI port or HDMI port on the monitor) when it should be powered down.

Dell's response is, "We don't test on Macs." That's not ideal, but not likely to change. However, since it behaves properly on most hardware, including some Macs, I'm hoping it's an issue that can be addressed through drivers, but the problem doesn't seem to be widespread enough, or the people experiencing it vocal enough to elicit a response from Apple. I hope I'm wrong.

Prove me wrong, Apple!


Edit: A couple other bits of information. I did try disconnecting all USB from the monitor with no change in behavior. If you connect the monitor via an analog method, such as a VGA cable, it will sleep, but that's hardly a viable workaround.