You are right, RAM is indeed a limiting factor. I have some corsair value ram 1333 and a corsair xms ram 1600. I was able to get better overclocks with the xms. It was not the ram speed. I was at something like 1000 something MHz on both, but the value one was crashing.
I am running with all power saving and turbo enabled.
I found that the limitation was the turbo. superpi which is single threaded takes the cpu to 4.2GHz (I think). Thats the max it could do at 1.4V vcore, 170 bclock. If it was just the other torture test(all 4 cores), it could go upto 175 bclock. At 175 if I used superpi it would crash with the value ram, but with the xms it would work. With value ram I was limited to 170 bclock.
Note - my info above is from memory. I too had done this a long time back, so I don't remember the specifics.
I have been running this for the past 2 yrs:
1.4V core (Yes I was unlucky. My processor is not a good overclocker)
2 x 4gb corsair value @ 1040 MHz (I think)
This gives 3.5Ghz output, turbo to 3.6GHz. turbo to 4.1GHz for single core.
And having more sticks of ram is a 'disadvantage'. Try your overclocks with a single one, after you are done overclocking you can add the rest one by one and see if its affecting anything.
Edited by inlife - 6/29/13 at 10:23pm