Kingston DDR3 2400 MHz works at 1600 MHz

[Krx]

Hello

I had this configuration:

INTEL Core i7-4770K 3.50GHz,
Gigabyte GA-Z87M-D3H (latest bios)
http://www.gigabyte.com/products/product-page.aspx?pid=4486#sp
Kingston DDR3 1600MHz 8GB (2x4) HX Beast KHX16C9T3K2/8X
Intel SSD 530 Series 180GB
Win 8.1 pro 64

I needed more ram so I purchased this one:
Kingston DDR3 HyperX Savage, 2400MHz, 16GB (2x8G),  C11, HX324C11SRK2/16

Previous RAM is taken out. New ram is installed in slots 1 and 3.
PC is OC-ed with Gigabyte Easy Tune @ 4.1 GHz
I wonder , why in BIOS says that ram works at 1600 MHz?
CpuZ PrintScreen attached.

In bios ram freq is set on Auto (1600). If I set profile1 (2400), it won't boot into OS, it returns into bios with warning message that something is not right.

Any suggestion(s)?

Tnx,
Regards

[dmdilks]

Try setting the speed and timings manually. The CPU will only support 1600. If that doesn't work. Try OC the CPU a little to see if you get them to run at that speed.