New Build Keeps crashing randomly!!

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Running windows 7? Check the event viewer! This might give some sort of readout that will tell you what is causing the error. Check that first to see if there is anything obvious. Look for any "CRITICAL ERRORS" or alike.

Also make sure that you are running all of the latest drivers for the motherboard, chipset, GPU ETC.

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Check the frequency that the RAM is running at. Most motherboards run the RAM at a default speed of 1333MHz or 1066MHz. The RAM you bought runs at a frequency of 1600MHz. Manually set the RAM speed to this in the BIOS and see if the crashes stop. My Core i5 2500 was having (very) intermittent crashes where the computer would become completely unresponsive just showing the desktop frozen on the screen. After manually setting the RAM speed to 1600MHz these errors stopped (knock on wood)  

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That power supply might be a little too small to power all those components. I'd check this by pulling out the GPU and running the system off the onboard GPU on the motherboard. If this stops the errors then you can possibly try underclocking the CPU and GPU and leaving the DVD drive unplugged to save power and get the system running stable. PLEASE NOTE: this issue is extremely unlikely to be causing your issue especially if your stress testing the computer and it doesn't crash. Stress testing is when the machine is using the most power.