Yes, changing the power management and SpeedStep/C-State settings (I did both at once before checking for Watchdog again) seems to have solved the issue. Like Eugene's linked thread says, reboot the Classmate and tap delete until you get into BIOS setup. I think it was under "CPU Settings" or something like that. Just disable the SpeedStep and first C-State option, then hit F10 to save and exit. Worked for us, hope it's so simple for you too
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