New build freezes when using 2x4gb ram

[monstur]

Just built my new rig, but it keeps freezing. I have used memtest86 and got passes for both my ram sticks when testing them one at a time. I would appreciate some advice because this is getting quite frustrating.
Specs:
i5 2500k 3.3g
evga gtx 560 ti
Corsair TW3X4G1333C9 XMS3 4GB 2 X 2 GB PC3-10666 1333Mhz
620w antec psu

forgot to add: mobo - MSI LGA1155/Intel P67 B3/DDR3/SATA3&USB3.0/A&GbE/ATX Motherboard P67A-G43 (B3)

 

[clarkjd]

So, do you have 4GB or 8GB of ram?

 

[monstur]

Sorry, 2x2gb of ram = 4gb. I've solve the problem already. Just a little tweak in the bios to raise DDRAM voltage to 1.55v did the trick.

 

[compulsivebuilder]

Do you have the RAM in the right slots? For it to work the way it is supposed to the DIMMs have to be in matching slots. You need to put them in the same colour sockets. If you put them in adjacent sockets (one blue, one black) the system won't work correctly.

Have a look in the manual - page 10 (in the English version).