I'm running Kubuntu 12.04 LTS, and consistently, the machine will not successfully warm boot. Right before the Grub menu should appear, I get a blinking cursor instead. Only a power off restart cures this issue. It doesn't matter which OS I do a warm restart from (I have 12.04 LTS, and Windows XP). I suspect a BIOS setting, but I'm not sure which one to tweak.