I've been blowing through graphics cards about every 12 months. Even with my new system it's been the same. I do play a lot of graphic intensity games. Could that be the reason for their early demise? The latest casualty is my GTX 560.
As another person mentioned, several things can cause this. If you live in an area with poor quality electricity [layman's term] your PSU will take a pounding.
The power supply was also mentioned. Most people do not know that the power supply is one of the most important components, yet spend as little as possible thinking any PSU is fine. You should at least get a power supply that has been 80Plus Certified. Check to see if your PSU name brand and model number are listed. Here is the link:
http://www.plugloadsolutions.com/80PlusPowerSupplies.aspx
One other thing that has me concerned is your PSU blows air INTO the case. It should be pulling air OUT of the case and expelling it into the room where your computer is located.
One other thing that I do is purchase a good uninterruptable power supply [UPS], it will help with some electrical problems coming to the computer.
A PSU is a little like a shock absorber on a car, however, the PSU helps to protect against electrical problems. You can use a surge protector, but plug your computer and monitor into the surge protector and the surge protector into the UPS, which is plugged into the wall outlet.
I cannot over state this, the quality of your power supply is vital. And, take it out of your case and figure out why it is blowing air into your computer case.
Edit:
Get cans of compressed air and clean all fans, heatsinks, and dust bunnies from inside the computer on a regular basis, twice a year if it is in a fairly dust/dirt free environment, more often if you live near a field that a farmer uses for crops, near any industry that dumps a lot of dirt and dust into the air.