What do I need to change on BIOS to get 1866 RAM?

Problem description (brief):

I had one stick of 4GB at 1333Mhz running perfectly. I bought Corsair Vengeance 1866 CL9 2x4GB to run in dual channel, but the motherboard sets it automatically to 1333. What do I need to change in my motherboard BIOS in order to get it running at 1866?

PC Info:
OS: Win 7 Professional 64bits
Mobo: GA-990FXA-D3
CPU: AMD FX-8150
Graphics: AMD Radeon HD 6950
OLD RAM: Kingston 1x4GB 1333Mhz
New RAM: Corsair Vengeance 2x4GB 1866 CL9 (9-10-9-27) CMZ8GX3M2A1866C9 http://www.corsair.com/memory-by-product-family/vengeance/vengeance-8gb-dual-channel-ddr3-memory-kit-cmz8gx3m2a1866c9.html
Corsair 750W

My motherboard memory compatibility list: http://download.gigabyte.eu/FileList/Memory/memory_ga-990fxa-d3.pdf
CPU-Z screenshot: http://i.imgur.com/jAspk.png
BIOS DRAM config: http://i.imgur.com/zRlSO.png (the only difference is that mine shows Trfc for DIMM1, DIMM3 90ns
If I modify the bus hz (I don't want, because I don't want to overclock my processor) I can't even access the BIOS, and if I modify the Memory Clock (x6.66, x8 or x9.33), PC does not boot, it says that I have an error due to overclocking and automatically sets it back to 6.66 (1333).

My approach:

I had one stick of 4GB at 1333Mhz RAM running perfectly, but now I have bought 2x4gb Corsair Vengeance 1866 CL9 (CMZ8GX3M2A1866C9). Which is supported according to the "supported memory list" in your website about my GA-990FXA-D3.

I have entered the BIOS and have seen that my bus speed (default) is at 200 with everything at auto for my processor (I don't want to OC it). So I tried to change de DRAM multiplier, which is by auto at 6.66, which sets the RAM at 1333. I tried to change it to 9.33x (1866) but when I restart I receive a BIOS error that there is a problem caused to overclocking and it sets the multiplier back to 6.66.

After that I tried to set the bus to 233 and the multiplier to 8x (1864) but that caused the PC to do not load (couldn't even change it) so I had to replace the old RAM and the motherboard set everything to default again.

The next the step was "Ok, I will try 1600", so I simply tried to set the multiplier to 8x (1600) with the new Corsair RAM. On boot it said the same as when I tried to set it to 9.33x.

Additionally, I want to let you know that the memory is installed in dual channel in slots 1 and 2 [NO][YES][NO][YES] how your manual explains.

I would like to receive detailed instructions on how can I run my memory at the recommended frequency and timings:

PC3-15000 (1866MHz) 9-10-9-27

(extracted from http://www.corsair.com/memory-by-product-family/vengeance/vengeance-8gb-dual-channel-ddr3-memory-kit-cmz8gx3m2a1866c9.html)

I'm looking forward to your reply, I need this hardware to work properly! I need your help this time, EXPERTS! I will try to help the community with my limitated knowledge (this is pretty deep for me) if I get this resolved!
2 answers Last reply
More about what change bios 1866
  1. if its like my 890fx board in dram control set memory clock to manual from auto and set multiplier to 9.33 instead of 6.66

    edit - you did remove the stick of 1333 correct?

    Also compare the auto assigned ddr3 timings to whats listed in the spd field. if they're different, make them match the spd.
    looks like you have to go to 9-10-9-27 timing at 1866 speed
  2. As stated above, adjust the timings to 9- 10- 9- 27 and if it still won't boot, try higher 11-11-11-30 just to see if it boots then
    set the command rate to 2t for testing, if it won't boot at 2t and 11-11-11-30, might just be a bad memory stkck, test each one separately
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