P45TS motherboard, two 2gb G.Skill 1333mhz sticks as dual channel.

In the board's BIOS display I can get RAM as 667mhz (DDR3 1333).

I cannot step beyond 667mhz. Board jumpers set for 1333. However, default jumpers gave same
inability to go beyond 667mhz. G. Skill web site says the sticks I have are 1333mhz.

Any hints?

Dick