That setup is so old that at this point you might as well upgrade all your internals. Get a newer board/proc/memory. A "new" 775 board by itself won't really do much good. You won't notice any real improvement in games if that's all you do. If you can't afford all of that right now, I'd say wait until you can. Don't toss good money down the drain in keeping an old rig on life support.