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If you want to CONNECT LCD monitor - you don't need DVI, if you want to USE it - you do
If you want to CONNECT LCD monitor - you don't need DVI, if you want to USE it - you do
Posted Dec 10, 2007 17:55 UTC (Mon) by alankila (subscriber, #47141)In reply to: If you want to CONNECT LCD monitor - you don't need DVI, if you want to USE it - you do by khim
Parent article: A pair of small Linux system reviews
You apparently have practical experience on dual-link DVI things. Will it work on Linux? What graphics hardware do you have?
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Dual-link DVI ? No FLOSS solutions at this time
Posted Dec 10, 2007 20:01 UTC (Mon) by khim (subscriber, #9252) [Link]
I'm using some Quadro FX card (lspci shows Quadro FX 3450) and it works "out of the box" (via DPMS) with nVidia drivers (I think I had trouble with "nv" drivers). Hopefully AMD (with community help) will have a compatible 100% FLOSS solution soon, but when the system was assembled we had no such promises and nVidia is less flacky...
Quite stable on this 64-bit box but as usual with binary drivers YMMV...
Some notes
Posted Dec 10, 2007 20:15 UTC (Mon) by khim (subscriber, #9252) [Link]
Dual-head is supported (I don't use it, but we've tested it and it worked) and there are commented modelines in xorg.conf:
Modeline "1920x1200" 155.0 1920 1984 2016 2144 1200 1203 1206 1212
Modeline "2560x1600" 348.16 2560 2752 3032 3504 1600 1601 1604 1656 -HSync +Vsync
Latest version of nVidia driver works just fine via just DPMS but apparently some older versions don't...
If you want to CONNECT LCD monitor - you don't need DVI, if you want to USE it - you do
Posted Dec 13, 2007 11:11 UTC (Thu) by job (subscriber, #670) [Link]
Why wouldn't it work? Dual-link DVI is a signalling standard so it's completely on the hardware side. Linux doesn't know anything about what kind of transport the signal uses just like it doesn't know what colour the cable is. (Perhaps you could ask the monitor using some PnP magic, but I'm not sure even the monitor knows single-link from dual-link DVI.)
DVI dual link
Posted Dec 13, 2007 18:29 UTC (Thu) by tialaramex (subscriber, #21167) [Link]
Modern graphics chipsets may actually expect the driver to set this stuff up. It might be as simple as flipping a bit, or it may be more complicated. There might be a provided firmware controlled part of the chip which does it for you, or there might not. As far as I remember there was a distinct piece of work for supporting things like dual-link in the radeonhd driver. So yes, Linux (or rather, the X driver) does know what sort of transport is being used, and indeed for some types of hardware it knows the type of connector (this information is in a firmware lookup table e.g. for the various DVI-like connectors) used, how the user is supposed to use it (USB's HID standard specifies things like "thumb control" even though obviously a hardware driver doesn't per se need to know that level of detail) even the color (Intel's HDA tells you this, though it's not always very accurate) The monitor definitely knows the difference, a display isn't required to implement dual-link DVI if it doesn't need it and so they don't. The pins for the second TMDS link can be omitted from the design altogether.