Whole computer crashes on games

[Denoahnator]

Well recently i built my first computer and I've been putting games on it and it's been working fine, but recently someone gave me portal and it worked well for about 30 minutes and then started crashing and it wasn't just a game crash, my whole computer froze and i had to press the reset button. I've also had my computer crash the same way on tf2 and dungeon defenders.

My Specs:
gpu: none, im using the integrated one on the apu untill i can buy one....
cpu: amd a8-5600k
mb: asrock fm2a75m-dgs
ram: CORSAIR Vengeance (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600
psu: rosewill fortress series 550w
hdd: WD Blue 500gb 200 RPM 16MB Cache SATA 6.0Gb/s 3.5"

I've updated the video driver recently too. Don't know if this matters but a few weeks ago when i turned it on it said disk read error press ctrl+alt+delete to reset, when i pressed it it took me to the bios and then started normally.

 

[amorenn]

Dedicated graphics at all?
Go to device manager -> audio devices and disable the AMD integrated through HDMI. It's incompatible with some games.

 

[C12Friedman]

Disc read error I usually associate with a failing hard drive although not the only possibility. Check the connections to your hard drive(s) - both ends, it may be a loose connection.
Hope it helps

 

[Denoahnator]

Dedicated graphics at all?
Go to device manager -> audio devices and disable the AMD integrated through HDMI. It's incompatible with some games.

ok so i went to device manager and there is no audio devices section just "sound, video, and game controllers" and in there theres amd high definition audio device, microsoft lifecam hd, and realtek high definition audio. which one do i disable? i know its not the lifecam cause thats my webcam.

Disc read error I usually associate with a failing hard drive although not the only possibility. Check the connections to your hard drive(s) - both ends, it may be a loose connection.
Hope it helps

the disk read error hasn't happened again so i don't thing that should be a problem unless it happens again, but ill keep that in mind