can't get 1280x1024 in Wheezy

[Steve Kleene <skdeb@syrano.acb.uc.edu>]

I installed Wheezy (testing) on a new desktop with an old Viewsonic 17
monitor.  The Intel i5 DH55HC processor has an onboard VGA chip.  I want an X
display resolution of 1280x1024, which the monitor did easily under Lenny
(but with an Asus GeForce2 MX400 video card).  Now I'm getting 1024x768, and
1280x1024 is not offered as an option.

Before burying you with data, here's the question: Is there any way I can get
1280x1024 without adding a video card?

xrandr ->
  Screen 0: minimum 320 x 200, current 1024 x 768, maximum 8192 x 8192
  VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) \
  0mm x 0mm
     1360x768       59.8
     1024x768       60.0*
     800x600        60.3     56.2
     848x480        60.0
     640x480        59.9     59.9
  HDMI1 disconnected (normal left inverted right x axis y axis)
  HDMI2 disconnected (normal left inverted right x axis y axis)
  DP1 disconnected (normal left inverted right x axis y axis)
  DP2 disconnected (normal left inverted right x axis y axis)

Gnome shows the same five resolution choices and just one choice of refresh
rate (60 Hz).  I have the xserver-xorg-video-intel package.

lsmod output includes this:
  video                  14605  1 i915
  output                  1204  1 video

I have posted the output of Xorg.0.log here:
  http://syrano.acb.uc.edu/sk/Xorg.0.log

It mentions many modules, including "intel" and "vesa".  It appears to be
trying the "intel" module, although I'm not sure.  Lsmod doesn't show a
module by that name, just i915.  For 1280x1024, Xorg.0.log says "hsync out of
range" or "vrefresh out of range".

Thanks.