Red Hat Bugzilla – Bug 419891
No signal with default mode.
Last modified: 2018-04-11 07:32:00 EDT
Description of problem:
Version-Release number of selected component (if applicable):
How reproducible: Always
Steps to Reproduce:
1. configure monitor automatically or set mode 1920x1280
2. start X server
Blank screen, after few seconds my monitor displays "No signal".
You know. :)
My monitor is not properly detected. I am unable to say to X server, that this mode:
Modeline "1920x1200"x59.9 193.25 1920 2056 2256 2592 1200
1203 1209 1245 -hsync +vsync (74.6 kHz)
is wrong. Even if I have in configuration statically configured horizsync:
HorizSync 31.5 - 74.5
this mode is selected. You can see, that this modeline is out of defined sync.
I am attaching my output from Xorg and xrand --verbose output.
I am able to set proper mode with this commend:
xrandr --output DVI-0 --mode 0x51
Mode 0x51 at 74 kHz works well, but mode 0x50 (which is still autoselected) does
I don't know, how to tell to X server to ignore this bad mode.
An beginner user is unable to use this mode and it is hard to me too, because I
need to type this commend after logon and my monitor is off.
Created attachment 284221 [details]
Created attachment 284231 [details]
Created attachment 284241 [details]
Created attachment 285091 [details]
Previous xorg.conf has been my test, where the problematic mode has been
Still not working:
Can I somehow help you?
Does vesa driver work? (so that at least you would have working computer :-))
I can try VESA driver evening, if required, but:
- proprietary fglrx driver works well
- default driver from Fedora works too, but I have to set 60 Hz mode manually
after each login (which is not trivial, because my monitor is OFF)
I think my computer works perfectly. DDC does not send this 59.9 Hz mode to ATI
card. I don't know, where this bad mode rises.
Current solution is to use proprietary driver, but I don't like it and want to
go back to open source driver.
that xrandr command could be probably added to ~/.xinitrc (see xinit(1) for more).
But it's a wrong solution for beginners, which have no signal after installation
of Fedora. May be it's a reason, why this bug has been marked as F9Target blocker.
Next proble is, tha I don't know, if it can't damage my monitor. Setting an
unsupported mode and then setting it back to an supported is not a good solution.
And last problem. GNOME's background is not properly set, when changing these
modes with xrandr. But it is another bug. Works well if this bug will be fixed.
Jan, I am not saying that this is the solution for this problem. Just as a
helpful bugmaster trying to make your life with broken Fedora slightly less painful.
I've just checked a fix into the upstream server. it'll take a while to come
back downstream, but it definitely should be in F9 final.
maybe if we do another F8 server release I can fix it there.
Should be fixed for F9 so removing blocker. it would be nice to have confirmation.
I can't install F9 on my machine before it will be marked as stable.
Is it possible to install a package from F9 to F8 to test this?
Or can I test this new update elsewhere on F8?
no its F9 only testable as it would require bringing in nearly all of F9, in
theory I could add the quirk to f8 but I haven't time at the moment.. you'll
just have to hope I fixed it correctly
My old computer is completely down (requires to press F1 on broken PS/2 port :-).
On my new machine opensource graphics drivers are not working and with
proprietary driver this bug does not occur.
I can't check this anymore, so if you think, it is fixed in F9, you can close
I'll close it as I think its fixed.