Gigabyte GTS 450 on ASUS M4A785TD-EVO

[Adremelech]

When I originally bought the card a while ago it worked fine for a week or two, but then it began locking up my system to the point where I couldnt even log in. It happens in both Windows 7 and Linux. The only way I could solve the problem was by putting the card into the PCI-e x4 slot instead of the PCI-e x16 slot. The only problem is that i'm afraid it limits my cards potential. Does anyone have any suggestions as to how to fix the problem? Here is my computers specs.

ASUS M4A785TD-V EVO AM3 AMD 785G HDMI ATX AMD Motherboard
GIGABYTE GV-N450-1GI GeForce GTS 450 (Fermi) 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card
AMD Phenom II X4 810 Deneb 2.6GHz Socket AM3 95W Quad-Core Processor
G.SKILL Ripjaws Series 8GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600
Rosewill Green Series RG630-S12 630W Continuous @40°C,80 PLUS Certified, Single 12V Rail, Active PFC "Compatible with Core i7,i5" Power Supply

Also, since one of my monitors uses VGA, I have a GT9500 in my PCI-e x16 slot currently.

 

[Gman450]

Does the problem occur with the 9500GT in your PCI-e X 16 slot?

 

[Adremelech]

No, the 9500GT works perfectly fine in both slots.

 

[Gman450]

So that would mean the motherboard isn't the problem here. Let's keep that aside for a while.
Did you check the video card temperatures at full load?

 

[Adremelech]

Yes, it gets to about mid 50C range unless F@H is running, but even then it only gets to 60C max.