Dual Core comparison

[Nocturne_sa]

Hi there,

planning on a major upgrade but facing a bit of confusion regarding CPU choice. I wanted to know how different are the core 2 duos from their predecessors core duos (Pentium d) apart from being 64bit. Ive got a tight budget and was hoping to go for 915 Dual Core 2.8GHz rather than the core 2 duo models...my board is the 975xbx so I can always upgrade to core 2 duos or something better in the future...
Ive heard that core 2 duos perform generally well and also run cooler than the core duos ... is that correct? Any advice will be much appreciated... my system components are ;

Intel 975xbx
Corsair XMS2 2gb Pc6400C5
His ICEQ3 X1900XT
Seagate 7200.10
ThermalTake Toughpower 650W

cheers

 

[Nocturne_sa]

cheers for the info.. so basically if i were to choose between e6300 and Pentium D 915 2.8GHz then I should go for e6300 even though the pentium d has 4 mb cache (as opposed to 2 mb on the e6300) and is clocked at 2.8?