Hi, today I got a motherboard at a car boot sale and it's a Gigabyte GA-945GCM-S2L. What is the best CPU that will work in it? I saw the core2 quad q9550 and 9650 and have also heard of modden 771 xeons. Is there any other options? Also, does the motherboard allow me to overclock? I have some ddr2 800mhz laying around but the mobo says 667mhz, could i get it to work?