System hangs whenever any kind of load is placed on the graphics card

Question

I recently built a new system and am having an issue with the whole system freezing whenever I place even a small load on the graphics card.  I've run memtest, prime95, and FurMark and the only one that gave me any issues was FurMark.  On the full screen 1080 test, the whole system just locked up after about 9 minutes. The strange thing is, the temperature didn't go abnormal and there was no apparent stress on the card. When it locks, nothing responds and I have to hard reset to bring the computer back.  I've had this happen while running 2 games at full screen after less than 10 minutes but neither one is especially graphics intensive.  I also had it happen once when I left the computer on overnight. 
My system:
Windows 8.1 Pro x64
AMD FX-9590 Vishera 8-Core 4.7GHz Processor
ASUS SABERTOOTH 990FX R2.0 AM3+ AMD 990FX Motherboard
G.SKILL Ripjaws X Series 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 1866
Thermaltake Toughpower Grand PS-TPG-0750MPCGUS-1 750W  PSU
MSI GTX 970 GAMING 4G GeForce GTX 970 4GB 256-Bit GDDR5 Graphics Card
CORSAIR Hydro Series H100i Extreme Performance Water/Liquid CPU Cooler
SAMSUNG 840 EVO MZ-7TE250BW 2.5" SSD 250GB SATA 6Gb/s Hard Drive
Western Digital Black WD2002FAEX 2TB 7200 RPM 64MB Cache SATA 6.0Gb/s Hard Drive
Maxtor DiamondMax 10 6L250M0 250GB 7200 RPM 8MB Cache SATA 1.5Gb/s Hard Drive
ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner
I also have a PCI-e Firewire card that I connect my Audio Interface to and a generic PCI wireless card. 
I've been trying to work through this for about a week and I feel like it might be the graphics card but this is my first decent build and I have never troubleshot anything like this.  Any insight you can give me would be appreciated. 

Answer 1

Ran IntelBurnTest at Maximum settings. The CPU temp maxed out at 67°C with the new case fan installed :
Processor: AMD FX(tm)-9590 Eight-Core Processor           
Clock Speed: 4.75 GHz
Active Physical Cores: 8
Total System Memory: 16282 MB
Stress Level: Maximum (14772 MB)
Testing started on 2/17/2015 12:51:15 PM
Time (s)      Speed (GFlops)      Result
[13:16:08] 1399.206   39.0676         2.924750e-002
[13:40:56] 1402.364   38.9796         2.924750e-002
[14:05:47] 1405.233   38.9000         2.924750e-002
[14:30:33] 1400.802   39.0231         2.924750e-002
[14:55:18] 1398.423   39.0895         2.924750e-002
[15:20:02] 1398.803   39.0788         2.924750e-002
[15:44:46] 1398.308   39.0927         2.924750e-002
[16:09:32] 1400.424   39.0336         2.924750e-002
[16:34:19] 1400.501   39.0315         2.924750e-002
[16:59:06] 1401.181   39.0125         2.924750e-002
Testing ended on 2/17/2015 4:59:08 PM
Test Result: Success.
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