Question DRam Clock Speed

[Emirkaon]

Hello guys i have a condsiderably old computer and im having problems with my dram clockspeed.

MB: Asus P5G41T-M LX3
Processor: Pentium E6500
GPU: Radeon HD 5750

And coming to RAM, i have one 2GB old Adata stick which is 1333Mhz and one Kingston ram with 4GB and 1600Mhz(kvr16n11/4).
I tried to single channel kingston, or dual channel them both. Theres no problem, they work together i get total of 6gb but i only get 533Mhz.
I tried to set DRam speed to 1066 which my motherboards maximum capacity.(Gets to 1333 with overclock)
But that didnt solved my problem.(Same thing happens when i single channel kingston).

Please help.

 

[Emirkaon]

Oh sorry i just forgot its half of the clock speed. Which makes 533 to 1066. Lol