I recently upgraded my system.

Old System:
MSI Sli V9 mobo
AMD Phenom 9500 Quad CPU
6gb ddr2 800mhz ram

New System:
ASUS Sabertooth 990fx r2.0 TUF mobo
AMD FX 8350 CPU
G-Skill 16gb ddr3 1866mhz ram

Stuff kept in new system that was in the old system:
DiabloTek 600w PSU
400gb Hard Drive
DVD RW cd drive
Geforce GTS 250 Video card

I had no problems with the old setup what so ever, other than it being outdated.

Everytime I watch a video in full screen the PC will shut off as if you unplugged it. No warnings, no BSOD, no errors. It happened while playing a game last night as well, but everytime I watch a video in full screen it happens.

I have been searching and reading problems about this issue for 7 days now. Posted on several forums and everyone has something different to solve it. I have uninstalled and reinstalled directx, nvidia video card drivers, flash player drivers, etc. I downloaded and use EVGA Precision X to monitor my GPU temps and use the ASUS Thermal Radar to monitor my motherboard and CPU temps. Everything seems normal:

CPU temps are 38-44c idle and 44-54c on heavy loads.

GPU temps are 35-45c idle and 45-58c on heavy loads.

However, I found that if I open a video and set the affinity to 1 or 2 cores it will work. So, my question is what does this mean? A faulty mobo/cpu? PSU? Overheating?

I am just concerned because I purchased this set up on 1/31/2013 and need to know if I have to send it back for a replacement before it's too late. I greatly appreciate all the help! Thank you.