It is released as a member of their family of virtualization products. VirtualBox (Oracle VM VirtualBox) is a virtualization package for x86, developed by Oracle corporation. The reason is simple that Parallels can access the graphic card that OS X already uses meaning you can play 3D games and use Adobe CS. Neither VMware Fusion nor Oracle VirtualBox can provide a well performing, smooth experience as Parallels. Meanwhile, VMware and Parallels are the two major players in the Mac consumer virtualization (commercial) software market. VirtualBox is the most popular VM software at the moment.
VirtualBox, VMware and Parallels are three of the most popular platform VM software. Most of such software allows having multiple machines on top of one physical platform. VirtualBox vs VMware vs Parallels Platform Virtual Machines (VM) are being used very heavily because they provide the ability to emulate a complete physical computer machine on top of another.
VideoCards In Bios we can set Optimus = Enable/Disable If Enable then we have two videocards Intel first and Nvidia second. It will work if Board-ID taken from iMac13,2. If Disable then we have only Nvidia card. But here there is contradiction with WiFi with required Board-ID from MacBookAir. In this case additional SSDT-3.aml will switch off Nvidia.