How to configure a desired screen resolution

[Jin Guojun]

I am not sure why you think this is BIOS issue. If this is BIOS issue, only one monitor should work with ASUS motherboard according to your theory.

Monitor A works on medium resolution, and Monitor B works on higher resolution but not works in the medium resolution individually.
However, when both Monitors are attached to the ASUS motherboard, then both can work in the medium resolution. From this point, neither the BIOS nor the Monitor is the issue.



On Wednesday, October 15, 2014 6:11 PM, Kevin Oberman <rkoberman at gmail.com> wrote:
 


On Wed, Oct 15, 2014 at 4:11 PM, Jin Guojun <jguojun at sbcglobal.net> wrote:

> The latest xorg 1.7.7 seems too smart to configure. It always uses what it thinks and ignores what xorg.conf file tells to do.
>
>
> I am using Vesa driver on 8.4-R / 10.1-RC amd kernel on the same hardware (ASUS A88XM-A motherboard) and experienced this difficulty.
>
> Two monitors: one has 1600x900 resolution and the other has 1920x1080 res.
> When attaching 1600x900 monitor to the system, xorg-1.7.7 X server configures the screen as 1600x900, which is nice and it is what I wanted.
> When connecting 1920x1080 monitor to the system, X server configures screen as 1920x1080, which is correct, but is will not give 1600x900 resolution regardless if the Modes "1600x900" is in Screen section in xorg.conf file.
>
> If attaching both monitors to the system, then both monitors will be configured as 1600x900, thus both monitors are capable to work in 1600x900 resolution.
>
> Now, how to tell (force) X server to use 1600x900 resolution for the 1920x1080 monitor?
>
> -Jin

This is not an X or Xorg issue, I'm afraid. The problem is that ASUS
has not updated the video BIOS for wide screen displays and, when
using VESA, only BIOS supported display sizes will work. Some vendors,
e.i. HP, have updated the BIOS on some systems to support wide screen
sizes. Lenovo had not when support for Sandy Bridge Intel graphics
became available. I keep meaning to switch the X server to VESA and
see if the latest BIOS upgrade fixes this, but I have not gotten to
it. This is particularly annoying as in both the HP and Lenovo cases I
am talking about laptops with wide-screen displays, so VESA did not
work right on the built-in display. I suspect it is less likely to
work on a system that does not come with a display.

There is simply no work-around for this. It is seems really silly in
this day of wide-screen display being the norm, but it cost money to
re-work BIOS and since Windows and Linux support the built-in graphics
on almost all boards.

I suspect you only hope is to move to a reasonable new FreeBSD
supporting KMS for Radeon devices. I believe you need to add
WITH_GALLIUM=YES to /etc/make.conf (echo "WITH_GALLIUM=YES" >>
/etc/make.conf) before building the kernel. You will also need to
update old xorg ports as NEW_XORG was only made default very recently.
--
R. Kevin Oberman, Network Engineer, Retired
E-mail: rkoberman at gmail.com