I have my i7-860 overclocked from 2.8 to 3.2 with an aftermarket heatsink attached. I am currently using G.Skill memory 2X2 GB DDR3 1333 10666 7-7-7-18 1T. I know that this memory is awesome for this CPU when it is at stock speeds, but at what point would I need to switch it with DDR3 1600 memory, or should I just adjust my FSB RAM 2:10 settings, or is it fine as is? I have this DDR3 1600 RAM (link below) in another computer I can switch it with, but I figured the timings were better with the DDR3 1333 and the CPU didn't need anything better at stocks speeds, but now that I overclocked it I dunno. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
As long as it remains stable, stick with the 1333 MHz. If my math is right, you've got your OC at CPU multiplier = x21 and bclk = 152? This would bring your speed to 152x21= 3.19 GHz.
If that's the case and you haven't adjusted your Memory Multiplier spd (which by default is 10) you're running your RAM at 152x10 = 1520 MHz. How am I doing?
If you want to keep pushing your OC and are worried the RAM makes it unstable, lower your Memory Multiplier (spd) to x8. At your current bclk you'll still be running at 152x8 = 1216 which will rise as you push the OC. Once you reach your desired OC, kick the RAM back up (be sure you've locked in your V). If it's not stable, then back it back down or consider switching. But you really won't notice much of a difference from the RAM anyway.