On 2011-08-02 14:59, Alex Deucher wrote: > On Mon, Aug 1, 2011 at 3:41 PM, Prof. Dr. Klaus Kusche > <klaus.kusche at computerix.info> wrote: >> Hmmm, what's about the opposite approach? >> To me, it sounds simpler and more logical when the kernel always creates >> one device node per output (or maybe dynamically per connected output), >> without any need for configuration or device assignment. > > You almost always have more connectors than display controllers (e.g., > you might have displayport, svideo, DVI-I and VGA, but only two > display controllers so you can only use two of the connectors at any > time). Also certain combinations of connectors are not possible > depending on the hw (e.g., the svideo and the VGA port may share the > same DAC, so you can only use one or the other at the same time).
Hmmm, for my purposes I was only thinking about new, current hardware, not about previous-generation cards, and only about digital outputs: * The professional, high-quality solution would be ATI's FirePro 2460: 4 mini Displayports, all active at the same time, single slot (passive cooling, < 20 W, so that's a great energy saver, too, competing with thin and zero clients, and it's silent and long-lived) * The XFX HD-677X-Z5F3 most likely offers most ports per Euro and space: 5 mini Displayports, all active at the same time, single slot, for less than 100 Euro (this would result in 16/20 seats with any quad-crossfire mainboard and 28/35 seats with some server mainboards if the BIOS is able to assign addresses to 7 graphics cards) Even the low-cost 6450 supports 3 and the 6570 supports 4 independent simultaneous outputs, so any ATI 6xxx card can drive all its outputs at the same time (and I believe that was also true for ATI 5xxx) However, cards with 3 or 4 digital outputs are hard to find in that price range... (XFX HD6570 is one of them) But you're correct, my suggestion above needs to be refined: One DRI device per display controller. Klaus. -- Prof. Dr. Klaus Kusche Private address: Rainstra?e 9/1, 88316 Isny, Germany +49 7562 6211377 Klaus.Kusche at computerix.info http://www.computerix.info Office address: NTA Isny gGmbH, Seidenstra?e 12-35, 88316 Isny, Germany +49 7562 9707 36 kusche at nta-isny.de http://www.nta-isny.de
