DPMS broken on ThinkPad T43 since update for amd64 support

[Kevin Oberman]

Since the update of DPMS to support amd64 on March 2, it has broken
rather badly on my ThinkPad T43 laptop. The problem showed up on
8-stable built on March 3 and is still present after an update to stable
of March 17.

When in vty text mode, after the idle normal delay, the display blanks,
but the backlight remains on, so the P in DPMS seems to be less than
effective. At that point, the non-graphics display is dead. It never
comes back when characters are entered. I can't get the display to come
back without a reboot.

I can, however, start X (and Gnome) and everything is fine. But
switching back to any vty results in a blank screen.

Any idea what happened and if there is a fix or workaround? Any data I
can collect?

The system is a uniprocessor Pentium-M:
CPU: Intel(R) Pentium(R) M processor 2.00GHz (1995.01-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0x6d8  Stepping = 8
  Features=0xafe9fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,$
  Features2=0x180<EST,TM2>
  AMD Features=0x100000<NX>

My display is:
vgapci0 at pci0:1:0:0:     class=0x030000 card=0x056e1014 chip=0x54601002 rev=0x00 hdr=0x00
    vendor     = 'ATI Technologies Inc. / Advanced Micro Devices, Inc.'
    device     = 'Radeon X300 Mobility (M22) (RV370)'
    class      = display
    subclass   = VGA
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634
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