Hi
Yesterday I tried to down-mode my Dell U2713HM from 2560x1440 to 1680x1050 via
xrandr --output DVI-D-1 --mode 1680x1050
After the switch, the Display came up with lots oft artifacts and totally mixed up. I was not able to switch to a textconsole, ctrl-alt-backspace did not work. There was no other way than to reboot the box. After booting, everything was looking OK until logging in to the same account. After logging in, problems returned as described. Other accounts do not suffer the problem - root login looks OK. This problem is reproducible and is stable against severeal reboots (Which is not usually the case with xrandr). For my main account it only went away after temporarily switching to nvidia-propietary driver and back again.
There are no entries in /var/log/messages whatsoever. Above command works fine when issued against the nvidia-propietary driver. I will recreate the problem this afternoon to generate a Xorg.0.log
What desktop? did you change res there also?
I use kde4. I have not yet tried out setting the display with kde-system-settings. I’ll do so now and report the results
As I said, the nvidia.proprietary-driver handles well against xrandr.
Why don’t you just use the proprietary driver then? 
Thanks again for pointing out the obvious to me 
Once I get immersed in the problem I tend to overlook simple solutions.
As for testing the switch to lower settings via kde-menu, this leads to similar results, a nice mondrianesque screen (screenshot as soon as mail from mobile phone arrives) and no way back to rl3 or text-mode-consoles.
As for using nvidia propietary driver, there are actually two reasons. First is, that I suspect this driver to render my vmplayer inoperable (see my other thread in this forum). Secondly, I think setting up nivida-driver from a nouveau-driven system is not a simple task for the average user (even if there are very good manuals). It has lots of tripwires to render a system inoperable for average desktop-users. Thus I think, that downscaling should be no sweat for the default driver delivered. Sadly, this is not the case.
Is somebody able to test downscaling from say 1920x1080 max reso to lower resos, to confirm that average layouts work? I’m aware of the fact, that this problem of mine is somewhat academic. My wife reported stability issues as well, this is what it logs (unhandled status) like:
/var/log/messages-20131123.xz:2013-11-22T16:04:41.249702+01:00 wingnut dbus[820]: [system] Activating service name='org.freedesktop.PackageKit' (using servicehelper)
/var/log/messages-20131123.xz:2013-11-22T16:04:41.307664+01:00 wingnut dbus[820]: [system] Successfully activated service 'org.freedesktop.PackageKit'
/var/log/messages-20131123.xz:2013-11-22T16:05:14.204161+01:00 wingnut kernel: 120.839796] nouveau ! PFIFO][0000:01:00.0] unhandled status 0x00800000
/var/log/messages-20131123.xz:2013-11-22T16:06:49.237057+01:00 wingnut rsyslogd: [origin software="rsyslogd" swVersion="7.4.6" x-pid="868" x-info="http://www.rsyslog.com"] start
/var/log/messages-20131123.xz:2013-11-22T16:06:49.237065+01:00 wingnut systemd[1]: Mounting POSIX Message Queue File System...
/var/log/messages-20131123.xz:2013-11-22T16:06:49.237103+01:00 wingnut systemd[1]: Mounting Huge Pages File System...
It seems I am stuck with nvidia and no vmplayer - at least for the time being
Hm, VMPlayer should work fine with the nvidia driver. Actually I only ever heard of people that couldn’t get it to run with nouveau.
Secondly, I think setting up nivida-driver from a nouveau-driven system is not a simple task for the average user (even if there are very good manuals). It has lots of tripwires to render a system inoperable for average desktop-users.
Not a simple task?
Just click on the 1-click install and it should work:
DKMS + NVIDIA 331.20 on openSUSE - Blogs - openSUSE Forums
And the official nvidia repo should be available any day now as well.
A 1-click install for that is here:
SDB:NVIDIA drivers - openSUSE
And yes, this is safe to do even from a nouveau-driven system…
Also soon the NVIDIA driver should be available from a repo. There has apparently been some delay in its deployment. After all 13/1 is only been out a couple of weeks and it is not uncommon to have a delay on proprietary software deployment
Thanks for the links to the repos. Actually I had planned to wait for the official repo, but problems for my wife got so bad, I did the compilation myself. Compared to the other methods mentioned, this is as I said no easy task.