Strange behavior I7 3930k, ASUS P9X79 – help needed! :doh:

I have 3 almost the same comps with next spec:
CPU: Intel I7 3930k
Cooler: Cooler Master Hyper 212 Evo
Motherboard: ASUS P9x79
RAM: Viper Xtreme Division 2 ddr3 2133 4x4Gb
GPU: ASUS ENGTX570 DCII/2DIS/1280MD5
PSU: Thermaltake 750W

On one I managed to put RAM on higher speed by putting timings higher and it works perfect. So, from original 2133MHz (11-11-11-30) I got 2400 MHZ (11-12-11-32) on the same default voltage 1.65 V.
On other two I got weary strange behavior. With exactly the same settings when I start comp it goes to black screen (freeze). After hard switching off (no chance for reset), I start again and there is message: overclocking failed press F1…… I press F1 and enter BIOS. Because I don’t won’t to change anything I chose exit and don’t save changes . Computer reboots and this time all is OK. Memory works on 2400 MHZ and you can work all day long with any problem even on 100% load. When you switch off comp story repeats -> next start computer will freeze and after hard switching off (4 seconds keeping off button pressed) reboots from BIOS.
Also when I enter BIOS to change something and reset from BIOS everything works fine until next start. Same problem is if I reset from Windows. Only option to get computer to work is if I start from BIOS!
Question is -> what goes wrong and is it possible to solve this problem. What I done up to now is to play with memory parameters and voltage with no success. BIOS is with latest update etc etc
P.S. the same behavior is no mater is it CPU overclocked or not. I tested on minimum speed 3200MHZ.
Thanks in advance for any idea