I just purchased a computer for some serious number crunching. I'm running
Excel 2003 under Windows XP Professional. The new machine has 4GB of memory
and a Pentium 820D (dual-core) processor

I am puzzled (and distraught) that this machine runs Excel computations 50%
*slower* than my laptop running a 1.86 Ghz Pentium M processor with 1 GB of
RAM and Windows 2000.

I expected the new machine to be at noticeably faster than my laptop. Is
this expectation unreasonable?

When I check the Task Manager, I notice that the dual-core machine never
uses more than 50% of the CPU for Excel, whereas my laptop uses up to 99%.

Did I make a big mistake with my choice of processor? Will the new machine
only use a single core for all computations in Excel? Even with one core,
should it be that much slower than my laptop?

To get the best performance from Excel, would the Intel Pentium 650 have
been a better choice? (Single core, but higher Ghz)

Any help would be appreciated.