Using a virtual machine is a lot like using a real one, since keyboard and mouse input work inside a guest OS much as they do within your primary one. A notable exception is the Ctrl-Alt-Delete keystroke combination — because of its special nature, if you want to execute the keystroke combo in a guest OS you must select it off the virtual machine's menu bar.
The lower right corner of each PW guest OS window displays a series of icons that indicate which system components (floppy, hard disk, CD/DVD, audio, network etc.) are present and/or active within the VM. When you want to use a CD or DVD disc with a guest OS, you can either use your system's physical drive or mount an .iso image of a disc instead. PW virtual machines will recognize many USB devices, provided the guest OS supports them.
When it comes to networking, VMs automatically bridge to your system's physical network adapter, allowing them to access resources such as a shared Internet connection. (You can also make VMs part of isolated networks or disable their networking altogether.)
When you're done working with a guest OS, you have the option to suspend it instead of shutting it down completely. Suspending a VM is a lot like putting a physical system into hibernation mode — the current state gets saved and picks up where it left off the next time the VM is started.
Parallels Workstation comes with an additional component called Parallels Tools that must be installed separately and that provides a number of VM enhancements. These include a clipboard synchronizer so you can copy the clipboard contents between primary and guest OSes. To facilitate the transfer of files, there's also a Shared Folders Tool that lets you create folders on your primary OS that are accessible (they look like network folders) within your guest OS.
Parallels Workstations Performance
A virtual machine will never be as fast as a real one, but performance is influenced by several variables like the specs of your system, the amount of RAM you use, and what applications you run inside the VM. We found all of our guest operating systems to be quite responsive, even when running all three at the same time (albeit on a 2 GB system, with 768 of that dedicated to the VMs). It's important to note that once you allocate memory to a VM it's not available to your primary OS while the VM is running. You can adjust the amount of memory allocated to a VM, but not while the VM is running or suspended.
Another performance caveat concerns graphics acceleration: PW can't virtualize the special hardware features of a graphics card, so instead it emulates a generic SVGA adapter that provides basic acceleration functions. It's more than sufficient to run most general applications, though any software that's demanding on graphics hardware (like many games) will probably run poorly or not at all. Video and audio playback worked just fine, however.
If you happen to own a system with CPU that includes support for Intel's VT (on Core 2 Duo and some Pentium D chips) or AMD's SVM (found on all AM2 socket processors), PW will provide better performance by running certain virtualization functions in hardware rather than software.
The Bottom Line
You can download an evaluation copy of the software through the Parallels Website. Unfortunately the trial version only works for 15 days, which doesn't give you a lot of time to try the product out. Registering the software after the trial period will cost $49.99, which isn't a lot considering all that the software lets you do.
(Microsoft offers its Virtual PC 2004 as a free download, but after three years on the market it's a bit long in the tooth.) Registered Parallels Workstation users can receive technical support via e-mail, but unfortunately Parallels doesn't offer an online support forum.
Overall, if you're looking for an easy and convenient way to run multiple operating systems without the expense and space requirements of physical systems, Parallels Workstation 2.2 certainly provides it.
