You indicate a 6700, to confirm this is a non-K model CPU? If so may want to try at 2800 or lower, your individual CPU (actually the MC (memory controller) in the CPU) may not be strong enough for 3000 sticks. Could try boosting the DRAM voltage + 0.05 with XMP enabled or drop the data rate and timings on the DRAM, initially would try 2800 at same timings