by nomad » Fri Aug 10, 2007 12:17
I have not exactly a problem but perhaps someone may have some insights. I have been running a 7600gs 512mb agp card and an Acer 20in LCD for a while. The monitor has only a VGA connection and it is hooked to the card's DVI output through a DVI/VGA converter. The 1680x1050 resolution was configured correctly on install and first boot with 3.3 with no issues. I have just recently upped to a Doublesight 24in LCD. The card's DVI connection is supposedly dual-link. The Doublesight monitor is single-link and came with a single-link DVI cable. I used this cable and have only 1024x768 resolution on the new 24in monitor, even after xorg.conf was edited to insert "1920x1200" in the "Screen" section:
===
Section "Screen"
# The Identifier, Device and Monitor lines must be present
Identifier "Screen 1"
Device "VESA"
Monitor "Generic Monitor"
Option "AddARGBGLXVisuals" "true"
# The favoured Depth and/or Bpp may be specified here
DefaultDepth 24
SubSection "Display"
Depth 8
ViewPort 0 0
Modes "1024x768" "800x600" "640x480"
EndSubsection
SubSection "Display"
Depth 16
ViewPort 0 0
Modes "1024x768" "800x600" "640x480"
EndSubsection
SubSection "Display"
Depth 24
ViewPort 0 0
Modes "1920x1200" "1680x1050" "1440x900" "1280x800" "1024x768" "800x600" "640x480"
EndSubsection
===
I have a second SATA drive with WXP installed and after booting into WXP, I set the new 1920x1200 resolution with no problems. Booting back in SL, which is in the first SATA drive, I still have the defaulted low resolution. Then I decided to put the new 24in monitor on the VGA cable, which is still connected to the DVI/VGA converter, hook that end up to the dual-link output of the card, restarted X and the new 1920x1200 resolution was up and running instantly.
My understanding is that dual-link cables are compatible with single-link connections, but is that assuming the same for single-link cable with a dual-link output? With the single-link cable, the extra pins on the card's dual-link output would just be ignored? Single-link outputs can power 1920-x1200 resolutions, according to many testimonies by those who have such set-ups. But like I said, I have a dual-link output and a single-link cable, which in order to successfully run 1920x1200 resolution on the new 24in monitor, I have to pass the output through a VGA converter and finally through a VGA cable. The new monitor does have both inputs -- DVI and VGA.
Dual-link output => DVI/VGA converter => VGA cable => 20in LCD (works)
Dual-link output => Single-link DVI cable => 24in LCD (no work in SL 3.3 but works in WXP)
Dual-link output => DVI/VGA converter => VGA cable => 24in LCD (works)
That's the gist of it. And the new 24in LCD is excellent, btw.