It could be a heat problem, thermal paste is inadequte (or too much), the heatsink/fan not properly seated, the psu is inadequate (720 watts for better performance), the ram might not be the required specifications.
You need to list all of your hardware including brand name, model, type, speed etc for a better analysis.
If the heatsink is a "dime" copper-based type, it is not suited to AMD, you need a heatsink that covers the entire surface of the cpu (as well as the proper application of thermal paste).
The memory was a package deal from Newegg so I asumed it was comcatible. No real time to get hot. The cooler and fan are bigger than the stock that came with the cpu.I focused there because I did notice the fan ad a slow windup. But since then I have tried out 4-5 fan I have acumilated over the years and they all behaved the same.I m now concerned something is faulty.
The initial roblem turned out to be the graphics crd. i=I replaced t and it started up. I got Win 8 installed and it ran for 2 days as I installed a few programs. Then it shut down and I have no idea what is wrong. I got my best help from the Gigabyte manual on the trouble shooting page. After bouncing around a while I realized I had not switched out the grqphics card. I did so and walla. The screen woke up. But now I am back searching. So no help here but now I am searching again.!!!