You may post your /etc/X11/XF86Config. There might be cases where 2 cards do not work together.
here it is. The included one specifies the voodoo driver, but I get the exact same result with the standard tdfx driver.
# XFree86 4 configuration created by redhat-config-xfree86 Section "ServerLayout" Identifier "Multihead layout" Screen 0 "Screen0" LeftOf "Screen1" Screen 1 "Screen1" 0 0 InputDevice "Mouse0" "CorePointer" InputDevice "Keyboard0" "CoreKeyboard" Option "Xinerama" "on" Option "Clone" "off" EndSection Section "Files" # RgbPath is the location of the RGB database. Note, this is the name of the # file minus the extension (like ".txt" or ".db"). There is normally # no need to change the default. # Multiple FontPath entries are allowed (they are concatenated together) # By default, Red Hat 6.0 and later now use a font server independent of # the X server to render fonts. RgbPath "/usr/X11R6/lib/X11/rgb" ModulePath "/usr/X11R6/lib/modules/extensions/nvidia" ModulePath "/usr/X11R6/lib/modules/extensions" ModulePath "/usr/X11R6/lib/modules" FontPath "unix/:7100" EndSection Section "Module" Load "dbe" Load "extmod" Load "fbdevhw" Load "glx" Load "record" Load "freetype" Load "type1" EndSection Section "InputDevice" # Specify which keyboard LEDs can be user-controlled (eg, with xset(1)) # Option "Xleds" "1 2 3" # To disable the XKEYBOARD extension, uncomment XkbDisable. # Option "XkbDisable" # To customise the XKB settings to suit your keyboard, modify the # lines below (which are the defaults). For example, for a non-U.S. # keyboard, you will probably want to use: # Option "XkbModel" "pc102" # If you have a US Microsoft Natural keyboard, you can use: # Option "XkbModel" "microsoft" # # Then to change the language, change the Layout setting. # For example, a german layout can be obtained with: # Option "XkbLayout" "de" # or: # Option "XkbLayout" "de" # Option "XkbVariant" "nodeadkeys" # # If you'd like to switch the positions of your capslock and # control keys, use: # Option "XkbOptions" "ctrl:swapcaps" # Or if you just want both to be control, use: # Option "XkbOptions" "ctrl:nocaps" # Identifier "Keyboard0" Driver "keyboard" Option "XkbRules" "xfree86" Option "XkbModel" "pc105" Option "XkbLayout" "us" EndSection Section "InputDevice" Identifier "Mouse0" Driver "mouse" Option "Protocol" "IMPS/2" Option "Device" "/dev/input/mice" Option "ZAxisMapping" "4 5" Option "Emulate3Buttons" "no" EndSection Section "InputDevice" # If the normal CorePointer mouse is not a USB mouse then # this input device can be used in AlwaysCore mode to let you # also use USB mice at the same time. Identifier "DevInputMice" Driver "mouse" Option "Protocol" "IMPS/2" Option "Device" "/dev/input/mice" Option "ZAxisMapping" "4 5" Option "Emulate3Buttons" "no" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Monitor Vendor" ModelName "A75f" DisplaySize 330 240 HorizSync 30.0 - 70.0 VertRefresh 50.0 - 160.0 Option "dpms" EndSection Section "Monitor" Identifier "Monitor1" VendorName "Monitor Vendor" ModelName "ViewSonic G70f" HorizSync 30.0 - 70.0 VertRefresh 50.0 - 160.0 Option "dpms" EndSection Section "Device" Identifier "Videocard0" Driver "nvidia" VendorName "Videocard vendor" BoardName "RIVA TNT2" EndSection Section "Device" Identifier "Videocard1" Driver "voodoo" VendorName "Videocard Vendor" BoardName "Voodoo3 (generic)" BusID "PCI:0:0b:0" EndSection Section "Screen" Identifier "Screen0" Device "Videocard0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Depth 16 Modes "800x600" "640x480" EndSubSection SubSection "Display" Depth 24 Modes "1280x1024" "1280x960" "1152x864" "1024x768" "800x600" "640x480" EndSubSection EndSection Section "Screen" Identifier "Screen1" Device "Videocard1" Monitor "Monitor1" DefaultDepth 24 SubSection "Display" Depth 24 Modes "1280x1024" EndSubSection EndSection
