Excel 2007 & Xeon, Quad core, non-xeon cores

[HansM]

Can anyone tell me if there is an advantage to a workstation having xeon
processors as opposed to a Core 2 Quad Q6700 for example?

I mostly use Excel and create very large worksheets doing lookups, sumif
functions and pivot tables. So I'm considering the Dell Optiplex using the
above referenced processor or a Dell Precision which uses Xeon 5130-5160 and
the E5320,E5345 etc.

Thanks for any comments in how either one of these may be better for Excel
2007.

Hans