ok i seem to have bad ram modules since tests were done and both windows memory diag and memtest86 points to ram problem, the good thing is that they are only a week old so i can have them replaced at frys, but the cheapest 4gb(2x 2gb) they have is a 1600mhz pair, is it ok for me to use that ram on my mobo thats 1333mhz recognizable?
RAM is backwards compatible when referring to the data transfer rate or 'speed'. So RAM rated at 1600MHz is fully capable and functional running at 1333MHz. RAM does have specific voltage requirement to run at advertised speeds. 1600Mhz rated RAM will require more voltage to run at the higher speed. RAM with higher advertised 'speeds' (1600Mhz.) will also require greater or laxed CAS latency and timing settings to achieve the higher speed. High Performance 1333Mhz. rated RAM should require less voltage, have tighter timings and be capaple of OCing to 'near' 1600MHz speeds. Anyway, RAM is backwards compatible so the higher rated RAM should work in the MB. You may have to install 1 DIMM and set the voltage properly in BIOS then install the remaing RAM with the correct voltage applied.
Run the MB through some RAM configurator to see RAM guaranteed to work in the board.
That is ok if the price is ok. Not all motherboard behave the same with specific memory so consult your mobo manual for that. I have tried using a OCZ memory on my gigabyte board and it goes well but some application misbehave until I change it to kingstons hyper X and the problem is gone.