This is the exact opposite of bug 21279.

The hardware is X700 PCIE.
kernel is 2.6.30 (gentoo-sources-2.6.30-r6)
xserver is 1.6.4
radeon driver is git f4407962cd7b272e0860319f11f6a6583ef226c2

I can run X fine if DynamicPM or ForceLowPowerMode are active but not if ClockGating is active. ClockGating alone is enough to cause a crash with the following X log:

==

X.Org X Server 1.6.4
Release Date: 2009-9-27
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.30-gentoo-r6 i686 
Current Operating System: Linux darksun 2.6.30-gentoo-r6 #1 Fri Oct 9 02:22:48 WEST 2009 i686
Build Date: 09 October 2009  01:15:20AM
 
	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Sat Oct 10 21:45:49 2009
(==) Using config file: "/etc/X11/xorg.conf"
(II) [KMS] drm report modesetting isn't supported.
  XRANDR name: VGA-0
  Connector: VGA
  CRT1: INTERNAL_DAC1
  DDC reg: 0x60
  XRANDR name: LVDS
  Connector: LVDS
  LCD1: INTERNAL_LVDS
  DDC reg: 0x1a8
  XRANDR name: DVI-0
  Connector: DVI-I
  DFP1: INTERNAL_TMDS1
  DDC reg: 0x64
Dac detection success
finished output detect: 0
finished output detect: 1
Unhandled monitor type 0
finished output detect: 2
finished all detect
before xf86InitialConfiguration
Dac detection success
Unhandled monitor type 0
Entering TV Save
Save TV timing tables
saveTimingTables: reading timing tables
TV Save done
disable LVDS
Static power management enable success
Dynamic clock gating enable success

Backtrace:
0: X(xorg_backtrace+0x3c) [0x8130ddc]
1: X(xf86SigHandler+0x52) [0x80d0d22]
2: [0xb7f46400]
3: /opt/xorg/lib/xorg/modules/drivers//radeon_drv.so(RADEONPMInit+0x1ce) [0xb799a33e]
4: /opt/xorg/lib/xorg/modules/drivers//radeon_drv.so(RADEONScreenInit+0x430) [0xb7957070]
5: X(AddScreen+0x1a5) [0x806e605]
6: X(InitOutput+0x1fc) [0x80ab26c]
7: X(main+0x1e1) [0x806ed01]
8: /lib/libc.so.6(__libc_start_main+0xe1) [0xb7b71711]
9: X [0x806e361]

Fatal server error:
Caught signal 11.  Server aborting


Please consult the The X.Org Foundation support 
	 at http://wiki.x.org
 for help. 
Please also check the log file at "/var/log/Xorg.0.log" for additional information.

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