i think i am using exactly the same configuration as you, i.e. an ATI Graphics Pro Turbo with a 21" ViewSonic P810 monitor. right now i am running 1600x1200 at 16bpp with no problems. i am using the mach64 driver. this is my XF86Config file:
# XF86Config auto-generated by XF86Setup # # Copyright (c) 1996 by The XFree86 Project, Inc. # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the "Software"), # to deal in the Software without restriction, including without limitation # the rights to use, copy, modify, merge, publish, distribute, sublicense, # and/or sell copies of the Software, and to permit persons to whom the # Software is furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included in # all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL # THE XFREE86 PROJECT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF # OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. # # Except as contained in this notice, the name of the XFree86 Project shall # not be used in advertising or otherwise to promote the sale, use or other # dealings in this Software without prior written authorization from the # XFree86 Project. # # See 'man XF86Config' for info on the format of this file Section "Files" RgbPath "/usr/X11R6/lib/X11/rgb" FontPath "/usr/X11R6/lib/X11/fonts/misc:unscaled" FontPath "/usr/X11R6/lib/X11/fonts/75dpi:unscaled" FontPath "/usr/X11R6/lib/X11/fonts/100dpi:unscaled" FontPath "/usr/X11R6/lib/X11/fonts/Type1" FontPath "/usr/X11R6/lib/X11/fonts/Speedo" FontPath "/usr/X11R6/lib/X11/fonts/misc" FontPath "/usr/X11R6/lib/X11/fonts/75dpi" FontPath "/usr/X11R6/lib/X11/fonts/100dpi" EndSection Section "ServerFlags" EndSection Section "Keyboard" Protocol "Standard" XkbRules "xfree86" XkbModel "pc101" XkbLayout "us" EndSection Section "Pointer" Protocol "PS/2" Device "/dev/psaux" EndSection Section "Monitor" Identifier "Primary Monitor" VendorName "Unknown" ModelName "Unknown" HorizSync 30-95 VertRefresh 50-160 Modeline "1600x1200" 202.00 1600 1644 1708 2140 1200 1206 1209 1244 Modeline "1280x1024" 135.00 1280 1300 1404 1664 1024 1027 1030 1064 Modeline "1152x864" 135.00 1152 1172 1300 1488 864 864 876 892 Modeline "1024x768" 85.00 1024 1032 1152 1360 768 784 787 823 Modeline "800x600" 50.00 800 856 976 1040 600 637 643 666 +hsync +vsync Modeline "640x480" 31.50 640 680 720 864 480 488 491 521 Modeline "640x400" 25.18 640 664 760 800 400 409 411 450 EndSection Section "Device" Identifier "Primary Card" VendorName "Unknown" BoardName "ATI Graphics Pro Turbo 1600" #Ramdac "ibm_rgb514" EndSection Section "Screen" Driver "Accel" Device "Primary Card" Monitor "Primary Monitor" SubSection "Display" Depth 8 Modes "1600x1200" "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 15 Modes "1600x1200" "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 16 Modes "1600x1200" "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 24 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" # Modes "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 32 # Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" Modes "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection EndSection Section "Screen" Driver "Mono" Device "Primary Card" Monitor "Primary Monitor" SubSection "Display" Depth 1 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection EndSection Section "Screen" Driver "VGA2" Device "Primary Card" Monitor "Primary Monitor" SubSection "Display" Depth 1 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection EndSection Section "Screen" Driver "VGA16" Device "Primary Card" Monitor "Primary Monitor" SubSection "Display" Depth 4 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection EndSection Section "Screen" Driver "SVGA" Device "Primary Card" Monitor "Primary Monitor" SubSection "Display" Depth 8 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 15 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 16 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 24 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection SubSection "Display" Depth 32 Modes "1280x1024" "1152x864" "1024x768" "800x600" "640x480" "640x400" EndSubSection EndSection --alex-- -- | I believe the moment is at hand when, by a paranoiac and active | | advance of the mind, it will be possible (simultaneously with | | automatism and other passive states) to systematize confusion | | and thus to help to discredit completely the world of reality. | -- TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to [EMAIL PROTECTED] . 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