Why are games crashing my new computer?

[ghastaphish]

So far I've only tried Civ 5 and League of Legends but the results are similar. I'll be playing for a while, anywhere between 5 and 20 minutes, and then the screen will go black and i have to restart the computer. In the case of Civ 5, there is a high pitched screeching noise that happens. Please, any suggestions on how to fix this? Is this an issue with my graphics card? I have the latest drivers for graphics card and motherboard.
my build is:
Intel Pentium G860
Windows 7 64bit
Asrock h77m micro atx board
Powercolor Radeon 7850 HD
Cooler Master Extreme Power Plus 500w
G.Skill value series 8GB 2x4 RAM
Seagate Barracuda 500GB HDD

I'm also using a Vizio 23inch HD tv for a moniter. Could the TV have anything to do with it, like maybe the resolution is wrong?

 

[rgd1101]

check temperature on gpu and cpu.

 

[smorizio]

could be two things a heat lock up or low power from your low end power supply on a high end video card.
try running msi afterburner set a fan profile that turns on the gpu fan to max speed at 50-60c. see if that helps...also try runing wiht the computer side panel off to see if it a heat issue. if the system still locks up try turning down the eye candy to see if your pulling more power then the power supply can give and it over heating and locking up. most large video cards i would have placed on a 600-650w ps. it not the total output you have to look at but the amp rating on the 12v line.

 

[ghastaphish]

I checked my GPU and CPU temp. During Civ 5 the GPU got up to 41 degrees and the CPU got up to 34 degrees. So, probably not a temp issue then?

 

[Kari]

In the case of Civ 5, there is a high pitched screeching noise that happens.

can you determine where the noise comes from? It sounds like it could be the graphics card, there is a small pietzo-electric siren on the card that goes off when the card doesn't get enough power to run properly. So it would mean your psu is acting up and maybe faulty.

 

[ghastaphish]

The screeching noise comes from my tv's speakers, so when i turn off the tv, the noise stops, and if i unplug the HDMI cable from the tv, it also stops, but resumes in both cases if i turn it back on/plug it back in.

 

[batty251]

could be the cpu not giving it enough power to run