While it is generally unwise to try overclocking any laptop's cpu, your graphics card can be software overclocked.
Use this program
http://event.msi.com/vga/afterburner/download.htmAfterburner is very self-explanatory. You will be able to change two settings; core clock and memory clock. The first dictates how many calculations your machine does every second in terms of graphics, the second controls how fast finished calculations are sent off to your cpu and monitor to display.
For the chip on the G73, it is most likely that you will run into core clock bottlenecks, though the core and memory clocks are fairly well balanced on all 460m and 560m cards.
Play a graphically intense game and see what kind of temperature your gpu reaches. If it stays below the mid 80's, it is generally safe to overclock, though you do this at your own risk.
Increase both core clock and memory clock in increments of 5 and 10 respectively, then game or benchmark for around 30 minutes. If everything goes smoothly, increase your frequencies.
Once anything odd at all happens during testing (e.g. brightness reset, screen glitches, driver crashes), go back down one level and keep your settings at that frequency; that is the farthest you are going to push your machine.
From my own experience, the cooling systems on these machines are done well enough that it is much more likely you will run into driver issues and crashes before you get any where close to the dangerous temperature zones for the physical gpu.
Personally, I keep my G53sx at 860 core clock and 1650 memory clock. I usually see an fps difference of around 6-7 versus default frequencies in gpu bottlenecked games.
