So after running WinXP as a VM under Hyper-V as my primary day to day machine for development, office applications, etc, I have decided to move to a Windows Server 2003 VM. My reasons for this are:

• Integration Services (Hyper-V's VM-Ware Tools equivalent) are supported under Windows Server 2003 SP2, where as you need SP3 of Windows XP, which is still in RC.
• Hyper-V supports 2 way SMP (more then 1 virtual processor) under Windows Server 2003. I feel that a 2nd virtual processor will make things allot more responsive.
• Server 2003 has less "stuff" turned on out of the box, and uses less ram. After a clean install, I have 89 MB of ram in use.
• I do not need any of the new features of Server 2008, such as 4 way SMP support under Hyper-V, DirectX 10, etc. The one thing that might be nice would be IIS 7 for development, but I would be looking at setting up a dedicated VM running SQL 2005/2008 and IIS 7 at that point. My immediate home development tasks will be focused on non-web applications (I think).

Even with only a single virtual processor installed and no integration services installed, the VM felt more responsive, and adding a second virtual processor and integration services has only increased this feeling. I set an 80% CPU resource constraint which corresponds to 40% of my systems overall CPU processing power. I have no technical reasoning for this other then 2 virtual CPU's at 80% should be more then sufficient for my needs, while keeping the overall system responsive, and allow for some other VM's if need be.

As part of my burn in process on my new machine, as well as something I do every day, I run Folding@Home. Usually I run with 3 folding instances, which leaves one of my four cores available for actual work. I've noticed when I'm actively using the XP VM and have 3 instances of folding running, that things seem sluggish at best.  With my new Windows 2003 VM and three folding instances running, the system is more responsive. I do not know why this might be (maybe the resource constraint I added?), nor have I done any type of benchmarking other then looking at Task Manager, but I'll take what I can get.

If I run into any gotcha's, I will post a follow-up, but I don't think I will. I've used Windows Server 2003 as a workstation before so I am very confident that I won't run into any type of application compatibility problems.