I recently OCed my i7 930 to 3.6 ghz and CPU-Z tells me that my FSB : DRAM is 2:6. Now I know that the i7 930 doesn't have a FSB, it has a QPI.
(I know that this is not an error with CPU-Z, and that CPU-Z is working correctly and shows it as FSB because that is how it is programmed, my question is not about CPU-Z.)
I know generally that with older CPUs (that did have a FSB), having the FSB : DRAM at 1:1 was best.
What I was wondering is, is this still true now that my CPU has a QPI instead of a FSB?
The RAM I have is OCZ Platinum OCZ3P1600LV6GK 6GB DDR3 3X2GB DDR3-1600 PC3-12800 CL 7-7-7-24. It is currently running at 6-6-6-18.
I got this RAM because I wanted to make sure it would not get in the way of OCing the CPU and I never expected to run it at 1600 with 7-7-7-24 timings.
What I had expected was for it to run at tighter timings at a lower speed to match the OC I managed to get to (I wasn't sure I would reach my goal). My goal was 3.6, and that was easily reached. I have no desire to go further than that, but I expect I could easily go well above 4.0 ghz. Of course this plan was made not realizing that my CPU didn't have a FSB, or knowing anything about QPI.
You should change the memory multiplier from 6 to 8, that should net you around 1376mhz ram. Play with your timings a bit to see how low you can go. That will probably be the best scenario for your setup.