For the last several months I've been running SW 2010 on a new MacBook Pro (Core i5 M 520 @ 2.40GHz) dual booting into XP. It's been running fine and outperforming my couple year old Dell Workstation by a few percent when benchmarked using Anna Wood's punch holder, averaging about 88. I decided to upgrade to Win 7, which I've been very happy with on the desktop and showed consistant performance with XP. However, I was very disappointed and confused to find that the Win 7 on the MacBook slowed down to 112 for the 32 bit install and 126 for x64. Test were run with consistant settings, i.e. verification on rebuild off, AC power, etc. The only difference I'm aware of is that I installed SP4.0 vs. 3.1 that had been on the XP install. I've fiddled with the Windows settings to maximize performance. The windows experience scores, for whatever that's worth, are higher than the desktop. I'm a bit confused as to what's going on. Anyone have any thoughts or suggestions?