The second part of that statement interests me as much as the first. ZDNet’s Adrian Kingsley-Hughes ran some informal tests on XP vs Vista vs Windows 7 beta 1 (as leaked, I presume), ranking them in order for a number of tasks. The results show that in general XP is slower than either Vista or XP on an AMD Phenom system with 4GB. Even on a Pentium dual core with just 1GB, which should favour XP, Vista was neck-and-neck with XP for speed (score of 57 vs 56, where less is better). Windows 7 came top in most of the tests.

I’ve done enough of these kinds of tests myself to know some of the pitfalls. Kingsley doesn’t mention whether UAC was on or off in Vista, or whether Aero is enabled, or how many background processes were running on each machine, or how many times the tests were repeated and whether there was much variation. It would also be interesting to know timings, rather than simple ranking. Finally, Kingsley’s tests seem overly weighted towards file I/O.

I’d also be intrigued to see a comparison of Vista as on first release vs a fully patched system.

Still, this does suggest (as I’ve argued before) that Vista is better than its reputation; and it is wrong to assume that XP will generally out-perform it.

That said, let’s not forget the dire performance of those early Vista laptops with 1GB RAM, a full helping of third-party foistware, and Outlook 2007. Even today, Outlook 2007 can kill the performance of a high-end system, as this recent comment shows: