Before creating a virtual machine (VM) on a computer, it's crucial to ensure that the CPU supports virtualization and that this feature is enabled in the BIOS (or UEFI) settings. While sufficient RAM and hard drive space are also important for running VMs effectively, and compatibility with the graphics card might be a consideration for VMs with intensive graphical requirements, the foundational step is to verify that the CPU supports virtualization and that this feature is activated in the BIOS settings. This is because virtualization technology, often referred to as VT-x (on Intel CPUs) or AMD-V (on AMD CPUs), is a prerequisite for running most virtualization software efficiently.
Reference:
CompTIA A+ Core 1 Exam Objectives Section 4.0: Virtualization and Cloud Computing