you can ONLY install that cpu's on the motherboard which are supported by the motherboard which they specify in their manual. For Example if your motherboard supports phenom and phenom 2 series chips, the you can install the fastest cpu in phenom 2 line but not FX or any other. If you want to install later ones then you may need new latest components as said by 'countmike' above. Always backup your data cause you 'may' have to upgrade BIOS if required if you are only changing cpu.