id get the 6 core...the problem with CPU tests, is you cant always trust them, theyre reliability, depends on what theyre designed to test for, and how. A lot of them, arnt designed around multiple cores, or even as many cores as they could. IVe seen some CPU tests give a single core CPU a higher score then a 8 core CPU, believe it or not, and ive also seen certain programs run better on a single core, then a multi-core. Depends on what they were written for. These days, more and more programs are written around multiple cores...what gives the 965 the performance boost is its 3.4 ghz clock speed, over the 6 cores 2.7, which is fantastic if your running software that requires high clock speed, but not necessarily good if your after multi-tasking.
Either way though, theyre both aging CPUs. Theyre good CPUs, but aging, and will both do you well, but I would use the 6 core, just from the standpoint I think it would give you better multi-tasking. (though, from your explanation, youd likely never even notice the difference between the two) and in the end, if you already have both CPUs, why not put in the one thats better-even if its just by the .1 the above CPU test gave.
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