I'm looking for 3 sticks of 4GB 1600Mhz (for my O/C) ram that has no extra heatsink (due to clearance issues) what would yous guys advise?

i'd advise you not waste your money on 12gb of ram
what are you doing that you need so much?!?
For those uses I would suggest the 12GB GeIL PC3-12800 1600MHz Value Plus CL9 Triple Channel kit (3x4GB).
This is for an X58 system, right?
How can you tell the RAM usage?

Oh FFS what is it with people saying "don't waste your money on RAM".
4GB is enough if you're browsing or gaming, but SOME of us have computers that aren't toys..[/QUOTE
With the current price of DDR3, any build I do for friends, most use W7 64, so my minimum install now is 8gb (2x4gb).
If you have empty memory slots then fill them, you can never have too much ram in my opinion.