Note: This appears to be a problem with Windows 8, no matter what host OS Virtualbox is running on.
I recently tried to install Windows 8 RP 32-bit in Virtualbox using Ubuntu 12.04 as the host. I have tried multiple settings for memory, hard drive size, etc. Every single time it has come up with this error
Your PC needs to restart. Please hold down the power button Error code: 0x0000005D Parameters: 0x0306170A, 0x756E6547, 0x49656E69, 0x6C65746E
I really like windows 8 and I would like to know how to fix this some time soon.