Question about ram

I got 2 gigs of ram that should support dual DDR setting at 400/200 yes ?
I cant get it working at 400/200 but the weird thing is i get 333/166 at 2T setting

If the 2 gigs are 4X 512 then they are probably double sided and the memory controller will not run them faster than 333. Check your manual. (Obviously, that's the last place I look after all else fails!)

Well i think it says it should handle 2 gig at stock speeds maybe im wrong i got 4X512 sticks in other words i wasted 250$ in buying 1 gig extra ram ?