a couple of odd behaviours.

[Clemens Koller]

Hi, Bruce!

Bruce Bowler schrieb:
> I have 4 machines connected with a single KVM (the KVM is part of the 
> problem but not all of the problem).
> 
> 2 machines run FC6 (call them M and A)and 2 machines run Windows XP (call 
> them B and E).
 >
> The M and A were recently upgraded from FC5 to FC6.  Since the upgrade, 
> if I don't do something X related on those machines for a couple of days, 
> Xorg either goes into a loop or I get a login screen, despite me not 
> having logged out.  My assumption is that the login screen follows Xorg 
> crashing but I haven't confirmed that for sure.  The other processes on 
> the system continue to run and I can SSH into the machine without any 
> problems, it's just X related things that don't work.  
> 
> Any suggestions for things to look for (or at) to try and nail this 
> problem down would be most welcome.
> 
> The other problem is at least partially KVM related.
> 
> If I "auto adjust" the monitor (Princeton VL1715) on M, it looks OK on E, 
> but the "working" part of the screen is shifted ~0.25 inches to the left 
> on A and B.  If I auto adjust while connected to A, it's OK and E but 
> shifted to the right on M and B.  If I auto adjust on B or E it's "close" 
> on the other one but off on M and A.  Is there a mechanism to tell Xorg 
> to "nudge" the screen left or right?

The position of the screen can vary with the signal timing from the video card.
(Usually, this happens with CRTs... TFT's usually compensate that during their
adjustments, but there might be limits.)

X can detect the capabilities of a monitor utilizing the so called DDC [1,2]
channel to adjust the video card's timing.
(DDC is usually just an I2C bus from the Video Card to an EEPROM inside of the
monitor where it can look up Type/Mfg and timing capabilities of the monitor)

You might try to switch DDC off and use fixed (optimized) settings.
So it shoudln't matter what KVM, CRT, <foo> you connect to your video card.

Regarding Windows... call Microsoft or shoot yourself into the foot.

Just my $.02.

[1] http://en.wikipedia.org/wiki/Display_Data_Channel
[2] http://xorg.freedesktop.org/archive/X11R7.1/doc/RELNOTES4.html#16

-- 
Clemens Koller
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