A couple weeks ago Legit Reviews was able to take our AMD Athlon 64 X2 4200+ AM2 processor and overclock it on air and water with amazing results. After this article was published we sat back and realized that we forgot about those readers who are looking to under volt their processors. With Home Theater PC’s (HTPC) taking off many computer users are looking to reduce the voltages to save power and lower thermal temperatures of the processor and ultimately the case. Even if you don’t care about temperatures undervolting your processor is a way to save energy and that means lowered energy bills! Today Legit Reviews takes the same processor we overvolted to reach an amazing 3.1GHz thanks to water cooling and go the other direction. Today we undervolt the same processor and try to find the lowest possible voltage the processor can run still stable at with the hopes of lowering power consumption and system temperatures.
Starting out at the factory settings we ran the 4200+ AM2 processor at 1.35 Vcore and observed the temperatures and power consumption and idle and during 100% CPU load. We then strarted lowering the voltage on the core down to the point where the system became unstable. Once we found where the system became unstable we were able to increase the voltage back up till it became 100% stable.
Let’s get started! Here is a CPU-Z shot with everything on the motherboard set to ‘auto’ meaning default settings. The vCore is set at 1.35V, but CPU-Z and other software utlities like SpeedFan detect the voltage as being roughly 1.232.