1 of 2 people found this helpful
All modern AMD processors vary frequency based on load and processor internal temp. Turbo mode is NOT available when the CPU is under heavy load. If the CPU or mobo VRM circuit is running excessively hot (above 61C for the FX-8000 / 9000 series CPUs), the processor frequency and vcore voltage will drop to 1.4 GHz. and ~.875v for a few seconds until the components cool and then go back to 4 GHz. This cycle will occur over and over until the load is reduced or the components receive more cooling. You can use OCCT or similar applets to record the processor frequency, internal temp, vcore, etc. Make sure that your CPU and case fans are set to 100% or maximum. You can temporality add a fan blowing on the VRM circuit to see if it takes longer to overheat if the VRM circuit is the problem. Note the dual video card will add a lot heat to the air inside the case so you need good airflow thru the case to prevent overheating.