rhgb not at full screen with intel driver

[Gianluca Cecchi]

hello, on my Dell SX280 with a 17" 1706FPV LCD I have the intial rhgb
graphic part that doesn't fit all the screen. Top sx corner is ok but
at the right and bottom sides I have black sectors. Something like a
1024x768 in a 1280x1024 available area.
After init part when X reloads I correctly get the gdm login screen.
I'm using intel driver, not the i810.
It began I think after latest X and X drivers upgrade:
May 24 10:13:57 Updated: xorg-x11-server-Xorg.x86_64 1.3.0.0-5.fc7
May 24 10:13:58 Updated: hal-devel.i386 0.5.9-8.fc7
May 24 10:14:01 Updated: gnome-vfs2-devel.i386 2.18.1-4.fc7
May 24 10:14:02 Updated: kudzu.x86_64 1.2.71-1
May 24 10:14:02 Updated: xorg-x11-drv-vesa.x86_64 1.3.0-6.fc7
May 24 10:14:03 Updated: xorg-x11-drv-i810.x86_64 2.0.0-3.fc7

Relevant part in my Xorg.con are

Section "Monitor"
        Identifier   "1706FP"
        HorizSync    30.0 - 81.0
        VertRefresh  56.0 - 76.0
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "intel"
#       Driver      "i810"
        Option "AperTexSize" "65536"
        Option "PageFlip" "true"
        Option "TripleBuffer" "true"
#       Option "AccelMethod" "EXA"
EndSection
Section "Screen"
#       Monitor     "1706FP"
        Identifier "Screen0"
        Device     "Videocard0"
        DefaultDepth     24
        SubSection "Display"
                Viewport   0 0
                Depth     24
        EndSubSection
EndSection

I'm fetching latest updates, but the only one that could in some way
be relevant is the kernel.
I'm at 3189 while I'm slowly downloading the 3194.
the others are cups, cyrus-sasl, glibc, gtk2, rhpl, specsp0, wine
Is it a known issue?
Gianluca