You get errors in OCCT, normally means not a ram problem, well, intel suggests
VID Voltage Range 0.8500V-V1.3625 http://ark.intel.com/Product.aspx?id=36503
You are already high on the vcore, what are your temps ?
You are overclocking your memory. That may be limiting your CPU overclock. You are running DDR2-800 RAM at 860 MHz. Adjust your memory frequency so that the memory is running two times the FSB frequency. At a 344 MHz FSB freq, your memory clock should be 688 MHz.
Intel's recommended max vcore is 1.3625 volts. Intel's absolute max is 1.45 volts.