VS2010 build times Win XP vs. Win 7

I am trying to determine which OS is the best one for VC++ VS2010. I know that Microsoft recommends Win7 x64 however I did some testing and the results are quite confusing:

Build times (single threaded compilation on q9650 CPU) of reference VC++ project under different OS:

Win XP 32bit: 00:02:50.95

Win 7 32bit: 00:03:09.99

Win 7 64bit: 00:03:19.05

Since the largest solutions I work with can take up to half an hour to build the ~ 1.15x slowdown on开发者_Go百科 Win 7 x64 when compared to XP 32 can cost almost 5 minutes which is not exactly negligible. I have turned off firewall, UAC, and Windows Defender on both Win 7 systems while testing. Are there any other options how to tweak VS2010 performance ? Or is this the best one can get from W7 + VS2010 ? Has anyone else experienced similar problem ? Note that this happens on machine with Windows Experience Index = 7.0 so it should be perfectly capable of running Win 7 and also no performance tweaks were necessary for Win XP.

I would have much preferred to use Win 7 (possibly x64 since the target machine will have 4GB RAM) as there will be some WPF projects soon, but the build slowdown is unexpectedly high in my opinion.

if you have a notebook, using 7200 rpm drive increases vs.net performance.