Cannot even get 1280x1024 through DVI (but yes on VGA!)
Crazy stuff here, it's 2011 and despite a new PC, new Linux OS (CentOS 6), new video cabling (DVI), I cannot even get 1280x1024 through DVI. But it works when I switch over to VGA (but that's somewhat fuzzier, hence the incentive to stay with DVI). After 8 long hours of every conceivable test I can think of (short of source code analysis/recompilation), I'm here asking for your experience.
We have three new HP Z210 workstations (i7-2600) with the default onboard graphics output (Sandy Bridge Integrated Graphics Controller, as seen by lspci -v) and a single DVI connector. When I connect analog video (through a DVI-VGA adapter to some Dell Ultrasharp 4:3 displays (1901FP or 1800FP) on the VGA input), I can easily get the desired native resolutions of these monitors (1280x1024) using
However switching over to pure digital video (DVI-D), Linux refuses, complains, and just fails at providing this very basic resolution.
CentOS 5.6 (32 bits): This is our main corporate OS that I have to get it working on
CentOS 5.6 (64 bits)
CentOS 6 (64 bits)
and it's the same problem on each of them.
On Windows 7, there is no such problem. Therefore it is absolutely a Linux OS-based problem.
I made endless attempts at changing /etc/X11/xorg.conf followed by gdm-restart, endless xrandr commands, cvt and gtf commands, and even modifying grub.conf with kernal arguments (vga=795 should give 1280x1024@24bpp). And did so much analysis of Xorg.0.log which basically leads me to believe these OSes are not sufficiently aware of this new Sandy Bridge Integrated Graphics Controller, in that VESA detection is not any good.
My ultimate question is, has anyone successfully driven an LCD screen at >1024x768 with DVI using CentOS 5.6 on a machine with the Sandy Bridge Integrated Graphics Controller? If so please reveal your secret (xorg.conf, etc.).