How to enable high resolution on external display with Radeon 7500 (FC6)?

[neojia]

hi,

I am running Fedora Core 6 on Thinkpad T42, which has a Radeon 7500. For the internal display it works very well with its highest resolution 1024x768. But when I am using an external display (such as Dell 1702FP), I cannot switch to a highest resolution. In FC3, it will automatically adjust to its highest resolution after plugging in.

So, is there any solution for my case?

Thanks,
Neo

[Michael]

Did you try using system-config-display or manually changing the resolutions in your xorg.conf?

[glussier]

If you are using the radeon open source driver, look for the "MergedFB" and "MergedXinerama" options in the device section of your xorg.conf file. The "Option "MetaModes" option will let you use both your Internal lcd and external monitors at different resolutions while retaining your 3d accelerations.

For example, heres 1 of my setups (Fedora Core 6) on a T42P with extended desktop setup with both monitors at different resolutions:

  
ection "Device"
        Identifier  "Card0"
        Driver      "radeon"
        VendorName  "ATI Technologies Inc"
        BoardName   "Radeon R250 Lf [FireGL 9000]"
        BusID       "PCI:1:0:0"

        Option  "MergedFB" "true"
        Option  "MonitorLayout" "LVDS,CRT"
        Option  "CRT2HSync" "30-96"
        Option  "CRT2VRefresh" "47-150"
        Option  "CRT2Position" "LeftOf"
        Option  "MergedXinerama" "true"
        Option  "MergedNonRectangular" "true"
        Option  "PanelSize"     "1400x1050"
        Option  "MetaModes"     "1400x1050-1280x1024"
EndSection

BTW, note that the above setup let's me use my Thinkpad with either the onboard lcd panel only or with a dual monitor with extended desktop. If this is not what you need, be more accurate with your question.