Originally posted on forum. I have tried to remove guest additions but nothing changes. Once a Windows VM starts when another presents already, the VM will hangup/BSOD. (VBOX GUI still alives)
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Just updated to 1.6.2. With AMD-V turned on, I can run any one of the VMs I have smoothly. However if I tried to open another Windows VM, all Windows VMs (new and current) will freeze or BSOD. If starting ubuntu VM and Windows VM simutaneously (with AMD-V), it's highly possible to have some error message during ubuntu initialization.
All the VMs I have can run properly without AMD-V. It seems that the current AMD-V support still have some problems dealing with multiple instances.
OS: Vista x64
HW: Phenom 9550, 790FX, 8G DDR2.