3 ram sticks - not possible?

[Max_s]

hi,
I have a PC runing on Asus p8h77-m pro motherboard with Crucial Ballistix Sport 8GB (2x 4GB) DDR3-RAM 1600 MHz 9-9-9-24 ram.

Now I bought a new Ram stick Crucial Ballistix Sport 8 GB (1x 8 GB) DDR3-RAM 1600 MHz 9-9-9-24. However, when I put this new stick into the board, the computer does not boot. It does boot with the new 8gb-stick alone though. I tried to exchange the positions, no success.

Should I change some settings in Bios? What else to try?

Thanks!

[Vicotnik]

Have you tried all possible combinations, or at least those that leave the same amount of memory in either channel? You could also try upping the memory voltage a bit or relax the timings.

[Lucky Luciano]

The MB might not support 2+1 configs. See page 33(2-13) of the manual http://dlcdnet.asus.com/pub/ASUS/mb/LGA ... -M_PRO.pdf

[Max_s]

Have you tried all possible combinations, or at least those that leave the same amount of memory in either channel?

Yes, I tried that.

[xan_user]

could be a simple bios setting to disable dual chan or similar. or might just need to load setup defaults in bios ...

also check the bios updates for the mobo, maybe they added more ram support.