i was a little confused with the passive & active DP->DVI adapters so i wikipedia'd for a little bit and came up with
Wikipedia (Displayport)
The video signal is not compatible with DVI or HDMI, but a DisplayPort connector can pass these signals through. While DVI and HDMI require separate clock signals, DisplayPort embeds the clock in the data signal. The data transmission protocol in DisplayPort is based on micro packets and is extensible for future feature additions, whereas DVI/HDMI transmission protocol is a Serial Data Stream at a multiple of 10 of the pixel clock rate.
So the "Active" DP->DVI takes the incoming DP packets, splits the DATA from the CLOCK SIGNALS, and formats them into the proper protocol and to the proper pins on the DVI connector
Then i started looking at the ATI unveiling of the 5870, and the slideshows of the architecture.
Now, display port has a little more bandwidth than dual-link DVI. so why are they using 2 of the DP-piplines for the DL-DVI port on the card?
i'm guessing 1 pipline is for the video data (un-packeted, and stripped of timing data so that it can be read by DVI), and 1 pipeline is used to simulate the clock signal that DVI needs.
so i'm guessing the cards we can get now are (2xDL-DVI,HDMI,DP) are configured on the card & firmware to look like this
i'm just confused why we can use the #5 HDMI pipeline & #6 displayport pipeline as a timing signal for the HDMI signal (DVI and HDMI share the same singal type)
or
are the 2 DAC's used in conjunction with the 2nd displayport-pipline configured for a clock signal, and there isnt a 3rd DAC to provide a clock signal for the HDMI output?
is this why we need a ACTIVE DP->DVI adapter to provide a clock signal for a 3rd (dvi or hdmi) display??
Sorry for the long post, but i've been reading all this stuff since it was first unveiled, and i need to get it out of my head and into the open before my brain fries thinking about it all.
everywhere i check they are sold out, wish i could of gotten ahold of one cause then i'd use a Apple miniDP-DVI active converter that i have for my macbookpro to connect to my 30" apple display, to test out some of these ideas.
-Ray