i'm looking into upgrading my motherboard and ram, i'm looking at getting the P5Q3 Deluxe board and the CORSAIR TWIN3XDHX 4GB KIT PC12800 1600M ram
If you're looking for more performance this will not help. Intel FSB based platforms do not benefit from the extra bandwidth DDR3 offers as the CPU has to pass through the north bridge to communicate with the RAM. The bandwidth of the RAM is therefore limited to the bandwidth of the FSB.
IMO, if you want more performance, and if you are gaming, your priority should be above all else your graphics card. It's definitely outdated even for your 17" monitor. The GTS 250
should be perfect for you.
You shouldn't need to upgrade your CPU right now, perhaps a little overclock? Which would give you a nice performance boost.