My old mobo has died GA-EP43T-UD3L and I'm thinking of replace it with Asus P5G41T-M LX, it's cheap and seems to fit what I need. Bit of a silly question but I noticed it said DDR3 1333(O.C.)/1066/800. I have 1333Mhz memory, why does it say (O.C)? is it only overclocked memory of that speed will work? my default speed of 1333mhz wont work? Thanks.
Your ram should work fine; you just may have to set the memory setting to manual and select 800 or 1600 for the speed, depending on the bios options. On some boards, the ram setting is half the actual speed. Then use cpuz to confirm the speed.