Xorg totally unusable with KMS and new Xorg on Sandy Bridge system: how to undo

[Warren Block]

On Fri, 8 Feb 2013, Thomas Mueller wrote:

> Thomas Mueller writes:
>
>>  I built the newer Xorg and it falls flat: goes to a nongraphic
>>  screen that is blank except for a rectangular cursor in the upper
>>  left corner, and now I want to get back to the earlier Xorg.
>>
>>  System is Intel Sandy Bridge with i7 CPU.
>
> Robert Huff responds:
>
>>         You don't mention your graphics chip explicitly, but building
>> libdrm with the KMS option was enough to prevent X from starting on
>> a Radeon HD 3300.  ("Experimental", indeed!  :-)
>>         Other will be able to help more if you could post the contents
>> of "/var/log/Xorg.0.log" and your xorg.conf file.
>
> My /var/log/Xorg.0.log has 0 bytes!
>
> To Andrey Fesenko <f0andrey at gmail.com>:
>
> Were you able to start X with
>
> # cat /etc/make.conf
> WITH_NEW_XORG=true
> WITH_KMS=true
>
> X.Org X Server 1.10.6
> Release Date: 2012-02-10
> intel(0): Integrated Graphics Chipset: Intel(R) Sandybridge Mobile (GT2+)
>
> (end of quote from Andrey Fesenko)

After adding those, graphics/libdrm must be rebuilt, and 
x11-drivers/xf86-video-intel must have the KMS option enabled and be 
rebuilt.  If you just added WITH_NEW_XORG, there will be other xorg 
components that need to be updated.