GMA 950 - intel - 1600x1200

Hong Liu hong.liu at
Tue Apr 15 18:53:25 PDT 2008

Can you change the mode to 1600x1200 after X startup by using
#xrandr --output VGA --mode 1600x1200 --rate 85?

It seems the EDID data from your monitor failed to set the prefer bit
for the additional video mode (1600x1200 at 85Hz):
(II) intel(0): Supported additional Video Mode:
(II) intel(0): clock: 229.5 MHz   Image Size:  360 x 270 mm  
(II) intel(0): h_active: 1600  h_sync: 1664  h_sync_end 1856 h_blank_end
2160 h_border: 0
(II) intel(0): v_active: 1200  v_sync: 1201  v_sync_end 1204 v_blanking:
1250 v_border: 0

This makes X server failed to select the 1600x1200 at 85Hz as the default
mode for your monitor. Would you please try the following patch?

diff --git a/hw/xfree86/modes/xf86EdidModes.c b/hw/xfree86/modes/xf86EdidModes.c
index 09d0039..167fe68 100644
--- a/hw/xfree86/modes/xf86EdidModes.c
+++ b/hw/xfree86/modes/xf86EdidModes.c
@@ -169,6 +169,11 @@ static Bool quirk_first_detailed_preferred (int scrnIndex, xf86MonPtr DDC)
 	DDC->vendor.prod_id == 2423)
 	return TRUE;
+    /* Hitachi CRT Superscan 753, reported on xorg list by Paul Novak */
+    if (memcmp (DDC->, "HTC", 4) == 0 &&
+	DDC->vendor.prod_id == 44066)
+	return TRUE;
     return FALSE;


On Tue, 2008-04-15 at 13:34 -0500, Paul Novak wrote:
> As requested, I'm sending the full log files as attachments.
> Here's a repost of the entire situation:
> I'm having trouble with graphics on a new computer with a new install of
> Slackware 12.0.  The motherboard has onboard video with the Intel GMA 950
> chipset.  My monitor is on older Hitachi CRT Superscan 753 with 1600x1200
> maximum resolution.
> If I use the intel driver (with dri and glx), the monitor comes up in 1600x1024.
> If I use the vesa driver (with no dri or glx) , the monitor comes up
> fine at 1600x1200.
> I tried LiveCD versions PClinuxOS and Knoppix, and both came up at
> 1600X1200 using
> the i810 driver; I tried the i810 driver as well with the same
> (1600x1024) results.
> I also download Slackware-current and have the same problem.
> I've tried all kinds of things to set the display resolution
> (including commenting
> out the  HorizSync and VertRefresh lines) with no success.  I'm not sure
> it's even possible (because 1600x1200 is listed under Future Video Modes)
> Googling has only confused me even more.  I can't figure out why
> I'm getting 1600x1024 resolution.  What if anything can I do to get
> my 1600x1200 resolution back so I can try compiz-fusion?
> Walt
> walt at
> _______________________________________________
> xorg mailing list
> xorg at

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