Pentium D 965 Extreme Edition - vs. - Pentium D E5200?

A Pentium D and a Pentium Dual-core aren't the same things - the Pentium D is an old Netburst architecture chip, whereas the Pentium Dual-core (like your E5300) are actually Core 2 Duos with less cache and lower FSB. Clock for clock, they're much faster than the old Netburst chips, which weren't very well designed.