Virtual Machines

A "virtual machine" (vm) is a file somewhere on your real hard disk. The Microsoft Virtual PC application will pretend this is a complete personal computer in itself. The virtual machine includes a virtual display adapter, a virtual floppy drive, and a virtual CD drive. You can attach one or more virtual hard disks to this virtual machine. This section illustrates how to create a virtual machine.

A virtual machine is a fictitous computer with emulated hardware. For example, a vm thinks it is running with a S3 Trio video display, regardless of what video display is really in your system. It thinks it has a Soundblaster 16 sound card. See the section titled "Emulated devices on virtual machines" in the Virtual PC help file for a complete list of what hardware a virtual machine thinks it is running on.

A vm includes a virtual floppy drive and a virtual CD drive. If you have an iso image of a CD or a raw image of a floppy disk, you can drag and drop that image onto the virtual floppy or CD drive and the vm will behave just as though you inserted a real CD or real floppy disk in a real drive.

Alternatively, you can link the virtual CD or floppy drive to your real CD or floppy drive. In that condition, the vm will see a real CD or floppy disk, just like normal.

Unfortunately, there is no USB emulation, so a vm thinks there are no USB ports. Note this does not mean you can't use a USB keyboard or mouse--those devices are captured by the Virtual PC application and translated so the vm thinks it is a regular keyboard or PS/2 mouse. But you're out of luck if you want to use other USB devices with a virtual machine.

Create a Virtual Machine

Step 1:

Start the Virtual PC Console.

From the menu bar, click File, then select New Virtual Machine Wizard.
Step 2:

Click Next to continue.
Step 3:

Select the option to Create a virtual machine.

Click Next to continue.
Step 4:

The virtual machine will be a vmc file. This file can be located anywhere on the host system. By default, the vmc file will be stored in a "My Virtual Machines" subfolder under our "My Documents" folder. The vmc files are not as large as virtual disk files. Nevertheless, let's store the vmc files on the E: drive along with the vhd files.

Click Next to continue.
Step 5:

This step isn't critical, but by indicating here that we're going to install Windows 98 in this vm, the wizard will recommend a ram setting in the next step.

Click Next to continue.
Step 6:

We can either choose to use the amount of ram recommended by the wizard (since we told it what OS we're going to install), or we can manually increase or decrease the amount of ram.

Bear in mind that the when the vm is running, the ram it uses will be taken from the system ram. If you plan to run several vms at the same time, you should have a lot of memory in your system.

Click Next to continue.
Step 7:

We've already created a vhd to use with this vm, so we'll indicate that here.

Click Next to continue.
Step 8:

This is name of the vhd file created earlier.

Check the Enable undo disks if we want to be able to discard changes at the end of each vm session. This feature permits us to start the vm in the same state at each session, without saving any changes from prior sessions.

Click Next to continue.
Step 9:

Click Finish.

This process creates a file called win98.vmc on the E: drive. The vmc may have other files associated with it if the undo disks option has been enabled or if the state of a running vm session is saved.

The vmc file can be moved or duplicated on other machines. When a vmc file is moved or renamed, it needs to be added to the Virtual PC Console. This is done by running the vm wizard and choosing Add an existing virtual machine in Step 3.

Remember, the vm runs on emulated hardware. Every installation of Microsoft Virtual PC emulates the same hardware, regardless of what actual hardware is in the system. That means you can take a vmc file created on one computer and run it on another computer--as far as the OS knows, the "hardware" it sees is the same!

Virtual Machine Settings:

Start the Virtual Machine Console.

Highlight the virtual machine just created.

Click the Settings button.

The Settings window will open. In this window we can highlight (and change) many of the basic settings of the virtual machine, such as the amount of memory that will be assigned to the vm. We can add or remove hard disks as vhd files.

author: Dan Goodell