does any one has intel e6750. how does it perform in multitasking and gaming?

Answer 1

Check the benchmarks here:
http://www.xbitlabs.com/articles/cpu/display/core2duo-e6850_5.html#sect1
http://www.xbitlabs.com/articles/cpu/display/core2duo-e6850_10.html#sect0

E6750 will just be slightly better than Q6600 quadcore in games but Q6600 will beat it in multitasking and heavily multi-threaded apps. If Q6600 is overclocked, it becomes unbeatable even by an overclocked E6850.
http://www.xbitlabs.com/articles/cpu/display/core2quad-q6600_8.html#sect0

Answer 2

Intel E6760 performs well in multitasking and gaming as long as you use a higher Ram. To take advantage of the speed it would be advised to use the dual channel of the ram slots instead of just using one side. This will take advantage of your index ratio by .5 or more. Multi-tasking runs fine with me coz i tried playing Generals and buring with a dvd and I find no glitch on the program execution. A factor I found also is on the video card that you would use it would help a lot on the execution of your video. I am using an ati 2600xt pro vid card.