In most cases you wouldn't notice the difference. In a CPU-limited situation you'd get around 10% better performance which is noticeable, but only barely. In GPU-limited situations you'd get no improvement. It's a close call.
For the 4670 you could get something like an Asus B85M-G, or an ATX B85/H87 mobo if you want more expansion slots. For the 3350P you could get a B75 mobo if you don't mind having only a single SATA3 port, otherwise go H77.