MSI mainboard with black socket to show AM3+
Some manufacturers have AM3+ support to some of their AM3 motherboards via a simple BIOS upgrade.Mechanical compatibility is there and it's possible for AM3+ CPUs to fit in AM3 boards, provided they can supply enough peak current. Another issue is the use of the sideband temperature sensor interface for reading the temperature from the CPU. Therefore, some CPU PWM fan pins may only run at full speed. Also, certain power-saving features may not work, due to lack of support for rapid VCore switching. *Note* that use of AM3+ CPUs in AM3 boards is not officially supported by AMD.