I had have the same problem. I use the instruction at the release notes:
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Blank screen with some ATI hardware
People with ATI display adapters may get a blank screen when loading X due to the driver being unable to initialize certain hardware. Upstream is working on it, and hopefully we'll be able to release an update for 7.10 soon after the release. In the meantime, add 'Option "LVDSBiosNativeMode" "false"' to the driver section of xorg.conf. Bug #132716
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After i change the xorg.conf i could start with a resolution of 800x600 pixels. Then i use the grafical tool to chance the resolution to 1280x1024 pixels, the normal resolution of my display.
I had have the same problem. I use the instruction at the release notes:
-->
Blank screen with some ATI hardware
People with ATI display adapters may get a blank screen when loading X due to the driver being unable to initialize certain hardware. Upstream is working on it, and hopefully we'll be able to release an update for 7.10 soon after the release. In the meantime, add 'Option "LVDSBiosNative Mode" "false"' to the driver section of xorg.conf. Bug #132716
<--
After i change the xorg.conf i could start with a resolution of 800x600 pixels. Then i use the grafical tool to chance the resolution to 1280x1024 pixels, the normal resolution of my display.
cheers
Sascha