You do realize that you are on an Apple/Mac forum right?
Yes, I would say you are in the wrong place for posting this. As a hardware enthusiast and one that has spent close to 15 yrs overclocking and tweaking my own gaming rigs, imho this is not the right forum for such questions. You need to be asking the experts and those that are overclocking the current gen equipment.
You may want to try some Alienware forums, and talk to folks that are actually overclocking their Alienware equipment, such as:
For general info about overclocking you should be going to overclocking specific and motherboard specific forums, such as:
ASUSTeK Computer Inc.-Forum-
Official GIGABYTE Forum - Index
There are a great many assets out there on the web that can be found with a little googling.
I would suggest that you do a great deal of reading on many of those forums prior to jumping in and asking willy nilly questions. Many of the folks on those type of technical forums are not going to respond very well to one that has not done any homework at all.
What you are embarking on is something that takes time to learn and a great deal of reading. You are going to have to take the time to learn. There is no instant gratification in this arena. You must know and understand what it is you are doing prior to beginning any of this on your own hardware unless you have the money to replace a CPU or GPU that you just fried.
At this point in time, you don't even know what questions to ask. Take my word for it. Spend a month reading all across the web on anything you can find related to overclocking and gaming rigs so that you are able to ask some educated questions and you'll be much more well received in those forums.
Oh, and just to answer your question: the risks of overclocking that specific computer are exactly the same as overclocking any other computer.