I'm way behind on understand what the new processor names and numbers 
mean.  Can any one tell me the differences in these or point me to an 
article that explains all this stuff?

My sister got a quote on a dell a while  back and the processor said
OptiPlex 380, Core 2 Duo E7500 with VT/2.93GHz,3M,1066FSB


I have a dell which says it has
3.0 gigahertz intel pentium 4
I'm guessing the computer my sister got is considerably faster than my 
Dell..  I'm wondering how the processors for the below board would compare 
to my sister's dell.

motherboard I've looked at on line says
Supports Intel Core2 Quad / Core2 Duo processors, 800/1066/1333MHz
and the cpu specs for this board say
CPU Socket
LGA775
CPU
Intel Core2 Quad (Q9000)
Intel Core2 Duo (E8000 and E7000)
Intel Core2 Extreme (QX9000)
Up to 4.0GHz speed and up to 12MB L2 cache

Can anyone put this in plain english?  This is perhaps to much to write on 
the list, so private e-mail is fine.
Any explanations greatly appreciated.

Butch
WA0VJR