Another problem is your video card might be bottle-necking your system. It is a little older card compared to everything else you upgraded.
just upgraded my motherboard, cpu and ram to the ones listed below. Playing some cod and i'm getting and annpyiong bit of lag, this didnt happen with my last components which was a duel core cpu and 2gb of ram i dont understannddd
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Try doing a fresh install of windows and install the latest BIOS update and also install all the chipset drivers.