I have a GT 72 with a 980m, last I checked you could OC memory clocks. Software overclocking has been restricted for a while to I think 135MHz on the core. Can't remember what memory clock restrictions are in place. So, if you want anything meaty you need to go down the flashing VBIOS route.
Aside from a quick play with nVidia Inspector some months ago I haven't really thought about OCing because I don't feel the need right now.
As for CPU, you want to look at Intel XTU. You should be able to bump a couple hundred MHz on to your turbo. Look for Meaker's GS30 nodding thread. He reduced his voltage and bumped clocks so all 4 cores run at 3.7GHz.