Computer shutting down while playing games?

I have a new Samsung Laptop running windows 8 on 64-bit, with an Intel i7 core processor, it has 8GB of RAM and over all works very well. Recently i have found how ever that i continue running into a problem, after a bit of playing a video game my computer totally shuts down and i have to restart it. The two games i have been playing lately that cause this is "Rust" and "War Thunder". Ill normally be maybe 15-25 minutes in game and the computer will just totally go black. I've tried just about everything i can think of to fix it on both games, reducing the graphics, shutting down all other programs and windows, v-sync on, deleting and re-installing both games, but the problem continues. I remembered however after getting this computer that when i tried to play Minecraft the same exact problem would happen, I fixed this by getting Java-64 rather than 32 and the problem went away completely. How ever if i'm already running 64 why would this still happen with these other games? I'm 99% positive it is not over heating since i always check and the laptop is no warmer than it normally is and like i said i try to make sure no other programs are running in the background. This never happens with anything else and i'm very confused on the matter, your help is much appreciated!

Its hard to tell if the hardware is overheating from the outside of the laptop. Download HWMonitor. Its free software that monitors your PC's temps. Launch one of those games in a windowed mode instead of fullscreen so you can keep an eye on HWMonitor and watch the temps. I have a feeling it is an overheating issue that is causing your problems.

It does sound like over heating issue. Sometimes, especially when the air vents are choked with dust, you might not be able to detect the temperature of the processor from outside.

If you really want to confirm this, you can use any free PC Temperature Monitor tools available online. These tools will be able to show if there's any drastic increase in PC temperature while playing games.

Solution:
Short term: You can use a low powered vacuum to blow out the dust from your your laptop cooling fan.
Avoid keeping the laptop on any soft fabric like pillows or thick table cloths (they can block air flow)
Keep a pencil or something similar (avoid any plastic objects that can melt) under you laptop next to the fan. This will improve airflow under the laptop and improve cooling efficiency.

Long term solution: Take you laptop to service and have the cooling fan checked and cleaned.

Before I start to tell you what your problem is, I know your NOT going to except my answer I'm not going to try to convince you other wise, it's your choice So here goes. Your problem is Windows 8 Period,

Now if you want to have a computer that is fast and furious, that does not crash or freeze up, does not get viruses then your going to have to JAIL break windows 8 and install Linux on your Samsung Laptop, I know you think Microsoft and Mac are the only computer operating systems in the world, They are Not. There's another Free operating systems that is far superior, and far more advanced,

Android, Chrome and Stream, are built from this Free operating system which is Linux operating system. Mac users don't know the operating system they use is built from a Free operating system called BSD, You know Samsung Android Chrome books, pads and phones are selling more that Apple iPads and iPhones, that should speak for itself how good Linux OS is,

Visit these websites and start learning
Linux Gamers news website
http://gamingonlinux.com

For Free up to date January 2014 Linux Operating Systems check these web links out
http://zorin-os.com
For a Linux Gamers release check out Sparky Linux Game Over scroll to the bottom of their webpage. It's Stream stream ready
http://sparkylinux.org

Then there's Valve Free Linux Stream Operating system you can download from their website, It has NOTHING to do with over Heating