FoxEye: Won't work. I have tested it on HDMI. Tested with DP as well. I have went thru on this road to find out what is good and what is not. ( i have monitor with vga and another with DVI-I as well) At DP , monitor is recognized but no signal.
What won't work?
The DisplayPort++ standard (read on Wiki or somewhere else) means that any *compliant* DP++ output can be attached to a DVI display with a *standards compliant* passive DP>DVI adapter.
If it doesn't work, then maybe either: you have a non-complaint DP cable (believe it or not, cheap DP cables might not be DP standard compliant, you can Google if you don't believe me); your DP output is not DP++; your DP++ source is non-compliant (unlikely).
The DP++ *standard* says that a DP++ source will recognise a DVI display and switch to outputting DVI signal instead of DP signal.
This is written in the DP++ standard.
As for the HDMI<>DVI statement. Yes, it does work. DVI and HDMI (video) are the *same* signal. 100%. I have used simple passive adapters *both* ways. It does work. Guaranteed.
If it doesn't work for you then you're doing something wrong. Because the standards define what is possible. And the standards say it *is* possible.
You can't say your anecdotal evidence trumps the written standards docs for HDMI, DVI or DP++, because I'm afraid the official spec is what matters, not what you've managed to get working or otherwise with your own equipment.
Oh and as Armageus said, you don't have a monitor with DVI-I. You have a monitor with DVI-D. Please learn the basics before giving advice.