I actually can relate with what you wanna do here. I have an FX-8350 and obviously, eight cores come up in Task Manager. Normally I would assign my tasks to as few cores/modules as possible. For example, when I'm browsing the Internet and running BitTorrent at the same time, I would assign both tasks to the same module, one thread for each of the two cores in a module. Doing this should help Windows decide to park the other modules so I can save some power. Obviously the FX is very different from the i7 in terms of what those 'cores' mean under Task Manager, but here, you see that it doesn't matter to which core I assign a thread in any given module. That particular module will work on both tasks equally and no task is given more priority over the other within that module. This isn't exactly what happens inside a physical i7 core, but you get the general idea.
AMD FX-8350 / Gigabyte 990FXA-UD3 (rev. 4) / 2 x G.Skill Ripjaws 4GB DDR3-1866 / AMD HD7770 1GB / TP-Link WN723N USB Wifi-N / Samsung 840 EVO 250GB / Hitachi 7K1000.C 1TB / LG ODD / Cooler Master GX650 / Aerocool VS3 / LG W2252TQ / Win7 64-bit