Thanks for the bug report.  We have reviewed the information you have provided above, and there is some additional information we require that will be helpful in our diagnosis of this issue.

Please attach output of dmesg command after gdm shows up (switch via Ctrl-Shift-F2 to get to the console), and X server log file (/var/log/Xorg.*.log) to the bug report as individual uncompressed file attachments using the bugzilla file attachment link below.

We will review this issue again once you've had a chance to attach this information.

Thanks in advance.

Does adding i915.powermode=0 to the kernel command line (in /etc/grub.conf) helps?

Since this bugzilla report was filed, there have been several major updates in various components of the Xorg system, which may have resolved this issue. Users who have experienced this problem are encouraged to upgrade their system to the latest version of their packages (at least F12Beta, but even better if the very latest versions).

Please, if you experience this problem on the up-to-date system, let us now in the comment for this bug, or whether the upgraded system works for you.

If you won't be able to reply in one month, I will have to close this bug as INSUFFICIENT_DATA. Thank you.

[This is a bulk message for all open Fedora Rawhide Xorg-related bugs. I'm adding myself to the CC list for each bug, so I'll see any comments you make after this and do my best to make sure every issue gets proper attention.]

Created attachment 369431 [details]
logs

Hello all, I met similar issue after upgrading from F11 to rawhide. The screen starts blinking (changing intensity up and low) on logon/logoff actions. It keeps blinking until you switch to console by pressing CTRL+ALT+F2 and back, after that X works ok.

Adding i915.powermode=0 to kernel cmd helps and blinking doesn't occur. 

My Xorg logs, dmesg and messages are attached: there two folders in the attached archive - one with i915.powermode=0 parameter, second - after rebooting without this parameter and performing few logins/logoffs.

$ X -version

X.Org X Server 1.7.1
Release Date: 2009-10-23
X Protocol Version 11, Revision 0
Build Operating System:  2.6.18-164.2.1.el5 
Current Operating System: Linux ryzh-netbook 2.6.31.5-127.fc12.i686 #1 SMP Sat Nov 7 21:41:45 EST 2009 i686
Kernel command line: ro root=UUID=459b7894-0498-42e3-9089-62065dd2b07b rhgb quiet SYSFONT=latarcyrheb-sun16 LANG=en_US.UTF-8 KEYTABLE=us
Build Date: 05 November 2009  07:43:20PM
Build ID: xorg-x11-server 1.7.1-7.fc12 
Current version of pixman: 0.16.2

Video device: 
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GME Express Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
	Subsystem: Micro-Star International Co., Ltd. Device 0110
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at dfe80000 (32-bit, non-prefetchable) [size=512K]
	Region 1: I/O ports at e0f0 [size=8]
	Region 2: Memory at c0000000 (32-bit, prefetchable) [size=256M]
	Region 3: Memory at dff00000 (32-bit, non-prefetchable) [size=256K]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
		Address: 00000000  Data: 0000
	Capabilities: [d0] Power Management version 2
		Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Kernel driver in use: i915
	Kernel modules: i915

00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03)
	Subsystem: Micro-Star International Co., Ltd. Device 0110
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Region 0: Memory at dfe00000 (32-bit, non-prefetchable) [size=512K]
	Capabilities: [d0] Power Management version 2
		Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-


It is MSI Wind U120 netbook.

Created attachment 369499 [details]
dmesg.txt without powermode changed

Created attachment 369500 [details]
messages without powermode changed

Created attachment 369501 [details]
Xorg.0.log without powermode changed

Created attachment 369502 [details]
dmesg.txt with i915.powermode=0 set

Created attachment 369503 [details]
messages with i915.powermode=0 set

Created attachment 369504 [details]
Xorg.0.log with i915.powermode=0 set

Victor, could you please install the latest kernel (http://koji.fedoraproject.org/koji/buildinfo?buildID=140298 ATM), intel driver (http://koji.fedoraproject.org/koji/buildinfo?buildID=138295), Xorg server (http://koji.fedoraproject.org/koji/buildinfo?buildID=140035), and mesa (http://koji.fedoraproject.org/koji/buildinfo?buildID=139790).

Does it change anything about the situation?

This bug appears to have been reported against 'rawhide' during the Fedora 12 development cycle.
Changing version to '12'.

More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

(In reply to comment #11)
> Victor, could you please install the latest kernel
> (http://koji.fedoraproject.org/koji/buildinfo?buildID=140298 ATM), intel driver
> (http://koji.fedoraproject.org/koji/buildinfo?buildID=138295), Xorg server
> (http://koji.fedoraproject.org/koji/buildinfo?buildID=140035), and mesa
> (http://koji.fedoraproject.org/koji/buildinfo?buildID=139790).
> 
> Does it change anything about the situation?  

Sorry for the delay. I already have all these versions installed except for mesa. I updated it and it didn't change the situation.

I found out that blinking takes place even when one trying to change the intensity manually and only switching to another workplace or console helps. In other word intensity changing doesn't work. I have no idea on how to debug it. Please advice.

the only thing I can see in logs are the following messages from kernel: 

Nov 20 02:21:24 localhost kernel: [drm:drm_mode_rmfb] *ERROR* tried to remove a fb that we didn't own
Nov 20 02:21:25 localhost kernel: integrated sync not supported
Nov 20 02:21:25 localhost kernel: integrated sync not supported
Nov 20 02:21:25 localhost kernel: integrated sync not supported
Nov 20 02:21:30 localhost kernel: integrated sync not supported
Nov 20 02:21:30 localhost kernel: integrated sync not supported
Nov 20 02:21:30 localhost kernel: integrated sync not supported


I can't say exactly if it can be related.

See also bug 531755 (also for MSI WIND)

Probably this bug and bug 531755 are duplicates. The only difference I see is 'Blocks' field. It is empty here and 'fedora-x-target' in bug 531755.

Would adding

i915.powersave=0

string to kernel command line (in /etc/grub.conf) help? If yes, then this is duplicate.

With this boot option, it complains : "i915.powersave=0 is an invalid option. ignoring"
It has no effect on flickering...

this flicker is a bug with brigitness

https://bugs.launchpad.net/fedora/+bug/415023

comment 80 is very clear

This message is a reminder that Fedora 12 is nearing its end of life.
Approximately 30 (thirty) days from now Fedora will stop maintaining
and issuing updates for Fedora 12.  It is Fedora's policy to close all
bug reports from releases that are no longer maintained.  At that time
this bug will be closed as WONTFIX if it remains open with a Fedora 
'version' of '12'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version prior to Fedora 12's end of life.

Bug Reporter: Thank you for reporting this issue and we are sorry that 
we may not be able to fix it before Fedora 12 is end of life.  If you 
would still like to see this bug fixed and are able to reproduce it 
against a later version of Fedora please change the 'version' of this 
bug to the applicable version.  If you are unable to change the version, 
please add a comment here and someone will do it for you.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events.  Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

The process we are following is described here: 
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

With Fedora 14, this bug doesn't happen anymore (MSI Wind)

Fedora 12 changed to end-of-life (EOL) status on 2010-12-02. Fedora 12 is 
no longer maintained, which means that it will not receive any further 
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of 
Fedora please feel free to reopen this bug against that version.

Thank you for reporting this bug and we are sorry it could not be fixed.