My pc shuts off while playing games

I was getting this with Nvidia's latest drivers. Perhaps you are suffering the same ill effects. Get BlueScreenView http://www.nirsoft.net/utils/blue_screen_view.html
check to see if it is indeed caused by the Nvidia drivers if so it will likely be nvlddmkm.sys in the logs. If so the newest beta drivers which can be obtained here http://www.geforce.com/drivers/beta-legacy fixed the issue for me and hopefully will solve your issue as well.

I notice you didn't list your power supply. What brand/model is it? I currently am having my computer black screen on me while gaming every once in a blue moon, and am in the process of isolating it (running furmark/Prime 95 at the same time). First run through of both of those I black screened and computer died. Upon reboot, I ran it again and it finished its 15 minute cycle without a hitch (nothing overclocked in my system as of yet). So again, what make/model is your power supply? Some brands advertise they are a certain power rating, but are nowhere near that.

I was thinking the same thing.

My power supply is a Topower nano series 500 series, the exact model number is TOP-500PM, please realize im a novice with pcs as this is my first pc build and I do not know alot of technical terms like overclocking and programs such as furmark/Prime 95.

My power supply is a Topower nano series 500 series, the exact model number is TOP-500PM, please realize im a novice with pcs as this is my first pc build and I do not know alot of technical terms like overclocking and programs such as furmark/Prime 95.

My power supply is a Topower nano series exact model number is TOP-500PM please realize im a novice with pcs so i do not know much about programs like furmark/prime 95

Understandable that you are new to the PC "techie" world--we all were at some point  
That power supply is relatively weak, and also has terrible reviews, but *should* hold up to what you're doing with it.

However, there is a VERY real possibility it is your power supply. To try to explain, your graphics card, as well as your processor both run on what is called a 12 volt rail. Inside your power supply, there are 2 of these. Your power supply says each of these rails are rated up to 20 amps (240 watts). Your graphics card pulls roughly 140 watts, while your processor pulls roughly 45-50 watts). Other components in your system also draw from these 12 volt rails. As to how much? Its hard to say the exact amount. Adding up all of these components with how much power they are using is *probably* overloading that low-end power supply. I would most definitely go to a computer store, and pickup a good power supply (450 watts or more on a good brand) and swap it out (make sure you can return it if you don't plan on keeping it if it does fix the problem). You can then go online and buy a better power supply if this fixes the issue (which I personally think it probably will). My personal favorites for lower-power power supplies are (not in any particular order) are Antec, Corsair, and thermaltake. There are other good brands out there too, but these are my favorite 3.

Post back if/when you do this as to if it fixed your problem!

Im looking to buy either this Thermaltake TR2 430W Power Supply (W0070RUC) PCI-Express, SATA, Dual 8cm Fans or Thermaltake TR2 500W Cable Management Optimized Power Supply (TR-500) you think either of these will do, Thanks again, all of this help is appreciated.  

Get a PSU from Antec, XFX, Corsair, or Seasonic.

The 500 watt one would do just fine. Keep in mind that all the PSU's tiny voices listed are good brands. I don't know why I left out seasonic earlier. I'm not a fan of xfx PSU's just like he isn't a fan thermaltake it looks like. With those 2 brands it seems its personal choice with a lot of builders.

XFX are rebranded seasonic's which are about the best PSU's you can buy.

That is true, but I had 3 bad xfx PSU's in a row. I probably was just unlucky, but it still jaded me from them.

its either the psu or overheating. check temps with hwmonitor. Probably cpu overheating causing the shutdown. check temps before you go randomly replacing what could be a perfectly good PSU.

OP has stated his temps stay around "40-50". Those temps are well within specifications.

Edit: Actually that does make me wonder, those temps you talk about... That is during gaming correct?

Last thing I'll say, for the $50 you were going to spend on that thermaltake, I would buy http://www.newegg.com/Product/Product.aspx?Item=N82E168... instead. Same price after rebate, and it's a higher quality PSU.

Thanks, but the thermaltake is going really cheap at 35 (after rebate) at canada computers so thats what im going for. thanks again.

Don't get a thermaltake PSU. its crap. Don't get a cx500 either. They are made with inferior capacitors. The XFX I linked is your best bet by far. It is made by seasonic which is as reliable and trustworthy as possible.

Hey thanks to all who posted turns out it was a problem with my psu i bought a corsair cx430 its working now but is thermaltake that bad of a psu brand? because when I to the store I was initially going to buy one but the guys at canada computers said that a thermaltake tr2- 500w was no better then my topower500w so any comments? But anyway thanks to everyone who posted helped alot.

Yeah, thermaltake is crap.

Well everyone's opinion of brands aside.., I'm glad we got it figured out man! Have fun gaming.