Does anyone know if it is safe to use the new Kingston HyperX Predator memory sticks that run on 2400MHz with Asus M5A99X EVO motherboard? This memory is not on the qualified vendors list and the fastest memory sticks on the list are running only at 2133MHz. Predator's voltage is 1,65V which is within the motherboard's specs.
It's perfectly safe. All the 2400MHZ rating means is that the memory is rated to run stable up to that frequency. But it will default to whatever freq the memory controller on the processor is. Ex: Phenom II's use a 1333MHZ controller. To run the memory faster, you need to O/C it.
The computer I intend to purchase the memory for is running a Phenom IIx4 955be CPU (I'm sorry for not mentioning this specification earlier). I have already overclocked it from 3,2 GHz to 3,8GHz. My current RAM is 4GB Apacer at 1333MHz rate. I am going upgrade this to 8GB with the Kingston 2x4GB memory kit that I mentioned in my previous post.
...I intend to purchase the memory for is running a Phenom IIx4 955be CPU
I really don't recommend any kits faster than DDR3-1600 for that CPU, and never a DDR3-2400 on any AMD CPU including the FX.
Even on a Bulldozer or Piledriver AMD maybe one step above rated (DDR3-1866) or DDR3-2133. Also, ASUS only lists support up to DDR3-2133 so unless a BIOS update includes a higher DRAM (Memory) Frequency the only way to achieve DDR3-2400 is OC'ing the 'FSB.' I can guarantee that you will not be able to run DDR3-2400 @ rated on your 955BE CPU, but you can run the RAM at a lower frequency of DDR3-1600 maybe DDR3-1866/2000. The problem quite often is DDR3-2400 (ultra high) frequency RAM has very poor non-rated CAS Timings i.e. they're not optimal running beneath rated frequency.
My recommended limits:
Phenom 4-core's DDR3-1600
Phenom 6-core's DDR3-2000
FX (any) DDR3-2133