virtualbox.org

Hello,

During 1 or few guests working, The host Windows suddenly going down (like blackout) and start rebooting.
Where can I check or fix?

VirtualBox 4.2.6 r82870
Windows 7 Professional SP1 32-bit
lenovo ThinkPad X1 Carbon, Core i5-3427U@1.8GHz 4GB RAM

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