Generally, Yes. Socket 775 systems are great for overclocking. However, if your bios doesn't allow you to set a higher front-side-bus speed or voltage, it's likely the motherboard cheaped out on a voltage regulator module, which will probably limit your success if trying to use programs like setfsb after bootup. The fact that you're using a 45nm CPU should mean that even in the case of a weak VRM, you should still have headroom of amperage to overclock it, as the board was probably designed to be able to handle a 65nm quad as well.
However, you'll probably get a better answer if you give more information, such as brand/model computer or motherboard you're using.