I've recently become interested in the hardware virtualization support that is present in modern processors, but I've hit what seems to be a rather large roadblock: relevant software seems almost entirely oriented towards server applications. This is a problem for me because my interests aren't really related to servers, but rather to running multiple OSes simultaneously in a desktop environment. One thing that is important in such a setup is that the "guest" operating systems can (when I desire) access the full hardware of the machine to perform resource-intensive operations like running a modern computer game. All the hypervisors within my reach (Xen, MS Hyper-V, KVM, VirtualBox, VMWare _, maybe a few others) seem to run the guest operating systems with an emulated VGA (or, for the higher end, sometimes VESA) video adapter, a poor (if present at all) sound card, etc. These things might be great for a server that uses virtualization for load balancing and fail-over capability, but it's horrible for a hobbyist that wants to tinker with such things as device drivers and alternate OSes. On the other hand, using "regular" VM software that sits in a guest OS of my choice does allow me to use the full computer resources in the host OS, but it eliminates the ability to run "real" device drivers and means I can't test resource-intensive software on multiple OSes since the guest OSes will have the same (or worse) emulated hardware as hypervisors provide. I could use an actual whole-system emulator to overcome the device driver issue, but they run even slower than traditional VM software. Are there any virtualization solutions that provide most of the benefits of multi-booting without the inconvenience of actually rebooting all the time?

Quote: This is a problem for me because my interests aren't really related to servers, but rather to running multiple OSes simultaneously in a desktop environment. One thing that is important in such a setup is that the "guest" operating systems can (when I desire) access the full hardware of the machine to perform resource-intensive operations like running a modern computer game.

The problem: your use case is a vanishingly small part of the market. There are plenty of developers who run an array of VMs as a test environment; I'm one of them. There are very few who would be particularly interested in doing it for a game. Games don't (or shouldn't) modify your system such that snapshots are a major convenience. Game testing often hinges on testing different *hardware* more than different OSes, so any serious testing will be done on multiple machines anyway.

That said, VMware ESXi might do what you want:

Quote: VMDirectPath I/O for virtual machines. Enhance CPU efficiency for applications that require frequent access to I/O devices by allowing select virtual machines to directly access underlying hardware devices. Other virtualization features, such as VMware VMotion™, hardware independence and sharing of physical I/O devices will not be available to the virtual machines using this feature.

Google turns up this:

Quote: vSphere 4 only announced support for few storage & network controllers because that is what *people* thought it was going to be used (and were tested internally) for but turned out that we have had few customers try GPUs, ISDN cards, SSL encryption cards, etc., and they worked fine even though VMware does not officially support those devices yet

I understand that it is a small niche for a market, but I'm kind of surprised that the open software groups haven't filled it, since it seems to fill so many small niches.

As far as running games under multiple OSes, that isn't for testing and development so much as just trying new OSes. I'm quite used to XP, but I'd like to also try windows 7 and see how it handles my games and how much work it is to adjust to it. I strongly dislike the direction microsoft has been taking with UIs since windows 2000, and it takes me a lot of work to adjust because of how frustrating I find the changes. I'm also interested in studying various linux distros.

As for snapshots, I don't really care for that ability all that much. It can be quite nice for some things, but my usage scenario is more about being able to run multiple operating systems full speed without buying an array of desktop machines.

Also, I currently don't own hardware that supports amd-v or intel vt-x. I'm looking at upgrading to something that does soon, but I'd like to have a plan of what software I'm going to run once I do. VMWare ESXi looks interesting, so I'll read more about it.