Hi again,
Before making any changes I would double check that you have the RAM in the correct slots on the motherboard. They should be inserted into slots DDR3_1 (furthest away from CPU) and DDR3_2. This is worth checking as it is easy to put them into the wrong slots, I know, because I've done that!
To alter the timings and the DRAM Voltage you need to be in the MIT Section of BIOS and go to the sub-menu DRAM Configuration.
Change the Set Memory clock from auto to manual and set the speed here, x6.66 for 1300MHz, X8 for 1600MHz etc.
Check that DCTs Mode is set to Unganged
Change DDR3 Timing Items from Auto to Manual this unlocks the options below it allowing you to input the SPD Data manually.
Leave 1T/2T Command Timing on Auto then input the correct values for your RAM in the subsequent rows.
If you are still having problems after doing this then I would recommend running MemTest to see if the RAM is faulty.