Intel Core i7
Launch: October 2008
Types: i7 800, i7 900
Speed: 2.6 GHz
Threads: 8 - Simultaneous Multithreading
Cache: 256 KB L2/core 8 MB shared L3
Memory: Triple channel DDR3 800/1066/1333 MHz
Core i7 is Intel's high end processor range. Core 2 Duo is budget processor range. In between both is Core i5. Core 2 Duo will soon be replaced with Core i3.
Core i7 uses new architecture and offers better performance than all Core 2 Duo processors.
New Features of Core i7
* Turbo Boost (automatic over clocking of up to 300 MHz)
* Hyper Threading (Core 2 Duo has no Hyper Threading)
Recommend to go for Core i7 if you can afford, or else Core i5. If you are in tight budget, Core 2 Duo range is also very good.