Computer Restarting Freezing Please Help

[4umresu]

For a few weeks now my computer has been freezing and restarting. It mostly happens during games but sometimes just browsing the web or doing nothing at all. When it happens it usually just stops and seems to reboot but gets stuck and never loads any bios/os screen. Once in a while it will restart right away but mostly after several hard resets or some elapsed time which varies it comes back on and usually after a while it stops having the issue but in the next couple days reoccurs. The only log information I have been able to find is: Event ID 41

I would greatly appreciate some help figuring out what is the problem and how to fix it. I received the computer 3 years ago from a friend and it has a water cooling system. Here are the specs:

Mainboard : Gigabyte GA-880GA-UD3H
Chipset : AMD 880G
Processor : AMD Phenom II X4 965e @ 3400 MHz
Physical Memory : 12288 MB DDR3-SDRAM
Video Card : NVIDIA GeForce GTX 480
Hard Disk : M4-CT128 M4SSD2 SATA Disk Device (128GB)
Hard Disk : Seagate ST320005 42AS SATA Disk Device (2000GB)
Monitor Type : Asus VE228 - 22 inches
Network Card : Realtek Semiconductor RTL8168/8111 PCIe Gigabit Ethernet Adapter
Network Card : Sundance Technology IC Plus IP1000 Family Gigabit Ethernet Adapter
Operating System : Windows 7 Professional Professional Media Center 6.01.7601 Service Pack 1 (64-bit)
DirectX : Version 11.00
Windows Performance Index : 7.4 on 7.9

Update 5/8/14 8:06pm
I ran a temp monitor on cpu/gpu while running the game that usually causes the crash/reset and it went from idle to the highest posted temp before freezing:
33c/90f
47c/116f
49c/120f
51c/123f

 

[YAYNEWCARD]

What PSU do you have?

 

[4umresu]

I ended up running memtest and found out one stick was bad. Everything works fine now, thank you.

 

[YAYNEWCARD]

I ended up running memtest and found out one stick was bad. Everything works fine now, thank you.

Good to hear you sorted things out

Regards.