You have installed your DIMMs in the correct (blue) slots.
When you increase the memory speed to 933 MHz (DDR3-1866), be certain that you're also relaxing the timings to the specified 9-10-9-28.
It may be necessary to increase the memory voltage from the default of 1.50 V to 1.60 V to get stable operation at higher speed.
If all else fails, operating your memory at PC3-12800 (DDR3-1600) speed isn't going to slow down your system a whole lot compared to PC3-15000 (DDR3-1866).
i7-2600K, H70, P8P67-M Pro, 16 GiB, HD7950, SSD, 3 HD, Blu-ray, X-Fi Ti Pro, Antec P182, S75CF, 3007WFP+2001FP, RK-9000BR, MX518
i5-3570K, GeminII-S524, P8Z77-M Pro, 16 GiB, HD7770, SSD, 2 HD, Blu-ray, InifiniTV4, NSK2480, 55" TV; Asus UX32VD