Windows 7: Random shutdown

My computer unexpectedly shuts down while playing some games. I'll play for about 5 minutes, then I hear a beep and the computer immediately shuts down. I thought that maybe it was because I was putting too much strain on my gpu (nvidia gtx 230), so i tried lowering my settings, but that changed nothing. This only happens for some games, and occasionally, the computer will not shut down. I am using an hp dv7t laptop with a core i7 720 quad core processor and 4 gigs ram.. Is this a hardware or software issue? And is it fixable/ avoidable?

Your computer might be overheating. Make sure to not have your laptop sitting on a pillow/blanket/pretty much any fabric.

You can also check event viewer for any errors that occurred directly before shutdown. This will help us tell you exactly what went on.

Overheating may definitely be a concern. Download a software called SpeedfanSpeedFan - Free software downloads and software reviews - CNET Download.com
The normal temperatures for most CPU's are between 30-70 degrees Celsius, when passing these temperatures, it automatically shuts down the computer to prevent damage.

After gaming on a computer for a while, it begins to deteriorate. The memory may become weak or other hardware devices may begin to fail, I have encountered this personally.

So the most I can do is get some kind of cooling fan and hope that it keeps my computer cool enough while playing? I'm not even sure that would work since my computer is running at 60c, without putting load on the cpu. Thanks for the info.

If your laptop is running at 60C without load, then there might be dust clogging the fan. 60C without load is not normal.

Do you have it sitting on a desk? Pillow on your lap? Coffee table?

I agree, take the covers off and get a can of air.

Use a compressed air blower to clean out the dust. At idle, your PC should run at an average of 40-49C.
Please if this does not work, reply.