Your psu is fine for both. I would go a bit higher if you want to overclock and your components will run better if the psu has headroom. If you really want to overclock, the psu should still be ok. Your psu also has the right connectors. You need a 6 and 8 pin for a 770 and the psu has 4 6+2 pin connectors, so you are good.
Hope this helps