Hi there.
When the G752VS OC Edition first came out, hardware wise it was seen as a very powerful machine however the Asus Software that was provided at the time of it's release caused it to throttle making it no better than the standard models. Removing the Asus Gaming Center software and then installing and using something else like ThrottleStop was the only solution to being able to overclock the machine properly and not having it throttle itself.
The problem seems to have come from the Asus Gaming Center software. The Asus Gaming Center software was designed to make going from Standard clocking to Extreme clocking modes very easy as it was set to do everything for you but there was something messed up with the voltage settings in it that basically broke the Extreme mode.
Eventually, Asus provided a fix called Turbo Gear Updater. Current version of it is V1.0.3. Installing that basically fixes the Asus Gaming Center software and Extreme mode now works like it is supposed to.
Sadly the damage was already done. Some people returned their machines and bought something else, while some ditched the Asus software for something else like ThrottleStop, I discovered this forum and used ThrottleStop too for a while. I didn't like the way you had to have it set to run as a scheduled task, but it did the job very well and was very configurable. If you like to tinker, this was it.
I just want to play games. So when I saw that the Turbo Gear Updater came out I decided to try it out and then reinstall the Asus Gaming Center software. If it didn't work out, I could always go back to ThrottleStop. Well, the Turbo Gear Updater did the trick and I am still running the Asus Gaming Center software too. All is well.
Having said all that, while the Asus Gaming Center software along with the Turbo Gear Updater works well, if you want to push your G752VS OC Edition to get every little bit out of it, ThrottleStop is the way to go. You gotta be careful though and know what you are doing.
Now if only Asus would fix the problems with the other drivers for the G752VS OC Edition like the touchpad!
Happy Gaming!