When you start the New Virtual Machine wizard, the wizard prompts you to select a typical or custom configuration.
Typical Configuration
If you select a typical configuration, you must specify or accept defaults for a few basic virtual machine settings.
How you want to install the guest operating system.
A name for the virtual machine and a location for the virtual machine files.
The size of the virtual disk and whether to split the disk into multiple virtual disk files.
Whether to customize specific hardware settings, including memory allocation, number of virtual processors, and network connection type.
Custom Configuration
You must select a custom configuration if you need to perform any of the following hardware customizations.
Create a virtual machine that has a different Workstation Pro version than the default hardware compatibility setting.
Select the I/O controller type for the SCSI controller.
Select the virtual disk device type.
Configure a physical disk or an existing virtual disk instead of create a new virtual disk.
Allocate all virtual disk space rather than let disk space gradually grow to the maximum disk size.