You can, but iirc, there might be issues with getting dual-channel to work when there's an odd-number of memory sticks (i.e. one stick in one channel, two sticks in the other). You might wind up just getting single-channel. Have to double-check with your motherboard's manual on that issue.
Also, at the moment, all triple-channel kits are designed for the X58 chipset, with the i7's internal memory controller. Because of that, it's been observed that many sticks don't need quite as much voltage to be stable as they did on older chipsets. As a result, the speed/timing/voltage ratings of the triple-channel kits might not work on older boards, without either relaxing the timings/speeds or bumping the voltages a little.
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