Veamos:
El 945G:
El G965:
Support for all "old" Celeron and Pentium processors (including dual-core processors) with 533/800/1066 MHz FSB, as well as all Core 2 Duo/Extreme processors
Dual-channel DDR2-533/667/800 memory controller, up to 4 DIMM modules with the total size of up to 8 GB (without ECC), Fast Memory Access and Flex Memory technologies
Graphics interface PCI Express x16
Integrated graphics core GMA X3000 (only G965) supporting Clear Video technology
DMI bus (~2 GB/s bandwidth) to the ICH8/R Southbridge
Up to six PCIEx1 ports
Up to four PCI slots
4/6 (4 in ICH8, 6 in ICH8R) Serial ATA II ports for 4/6 SATA300 devices (SATA-II, the second generation of the standard) supporting AHCI mode and NCQ (ICH8R only)
Support RAID (ICH8R only) 0, 1, 0+1 (10) and 5 with Matrix RAID function (the same array of drives can be used in several RAID modes — for example, two drives may form RAID 0 and RAID 1, each array will have its own part of the drives)
10 x USB 2.0 devices that can be disabled individually
Gigabit Ethernet MAC controller and a special interface (LCI/GLCI) for a PHY controller (i82566 for Gigabit Ethernet, i82562 for Fast Ethernet)
High Definition Audio (7.1)
Binding for low-speed and outdated periphery, other things.
Otra diferencia es el Intel Fast Memory Technology:
Otra diferencia sería la capacidad de overclock, la del Intel P965 es claramente superior (hasta 500Mhz o más de bus) mientras que el 945 está limitado a 299Mhz de bus.
También creo que el 945 no tiene ni tendrá soporte para procesadores QuadCore, cosa que el 965 ya tiene actualmente.
De qué diferencia de precios estamos hablando ? Para qué usarás el equipo ? Tienes planeado hacer overclock ? Eres exigente con los resultados a obtener ?
A groso modo la "única" diferencia es el rendimiento (sobretodo de la memoria RAM) y la capacidad de overclock.
