difference between core 2 duo and core i7?

They're certainly comparable, although the i7 is significantly more powerful.

In rough progression, Intel's desktop processors go:

Core 2 Duo

Core 2 Quad

Core i3 (dual cores)

Core i5 (mostly dual, but the i5-750 is a quad)

Core i7 (quad and 6 core varieties)

There is some overlap in performance between Core 2 and Core i3/i5. Core i7's are the undisputed performance champions in the Intel line. Use a benchmark chart like this to figure out which is best for your needs: http://www.cpubenchmark.net/cpu_list.php

Intel middle i7 Codenamed: Bloomfield – Nehalem Fabrication: 40 5 nm practise set: X86, X86-sixty 4, MMX, SSE 4.2 Socket: LGA 1366 Bus: speedy direction Interconnect RAM: DDR3 Chipset help: X58 Intel middle 2 Duo Codenamed: Conroe, Allendale, Wolfdale – middle 2 Fabrication: sixty 5 nm / 40 5 nm practise set: X86, X86-sixty 4, MMX, SSE 4.a million Socket: LGA 775 Bus: 1333 MHz FSB RAM: DDR2 Chipset help: 965, P3x, G3x, P45, X48 rationalization: (distinction between Intel middle i7 and middle 2 Duo) - The middle i7 is a thoroughly new shape that's lots swifter and greater effective than the middle 2 Duo. at the instant in basic terms the middle i7 920, 945 and 965 XE variations are available. Of that the middle i7 920 is accessible at merely $284 which makes it a super purchase. It grants greater effective overall performance than tremendously much all middle 2 Duo processors. Google is your buddy.

Core i7 is the successor to the Core 2. As for what's comparable, which processors are you looking at? i7 and Core 2 are only brand names.

The two are made for different sockets so you cannot upgrade to an i7 without getting a new MOBO also. You would be better of getting a better Video card and increasing the RAM.