Hello all this is my first post and I have a bit of a problem! I am putting together a new system and think I may have made a mistake. I bought the Asus M4A78T-E motherboard which is compatible with DDR3 12800 1600. I rechecked this on crucial's memory compatibility tool and ordered myself a nice set of 4GB kit (2GBx2), Ballistix 240-pin DIMM, DDR3 PC3-12800. Link - http://www.crucial.com/uk/store/partspecs.aspx?IMODULE=BL2KIT25664BN1608 Now here comes the problem. I've bought an AMD Phenom II x4 945 3.0ghz to go with this system, it arrived today. I've now found out that the AMD Phenom II x4 945 3.0ghz only supports up to 1333 DDR3. I know the system will underclock and everything will run ok BUT my question is - Will it have an adverse affect on the system's performance compared to running 10600 1333? And why? (I don't understand memory timings too much) Cheers in advance, Keth.