System Management Controller

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The System Management Controller (SMC) is an internal subsystem introduced by Apple Inc. with the introduction of their new Intel processor based machines in 2006. It takes over the functions of the SMU.[1] Apple has released updates for this system in order to address power or sleep issues in several recent models.[2]


The SMC controls power flow and fan speed, like the SMU before it. The main objective is to keep the machine running normally with minimal noise. It also enables enforcement of the Mac OS X End User License, allowing it to identify when it is running on non-Apple hardware,[3] although this can be circumvented by using third-party hacks.[4][5] The SMC should not normally need to be reset at all. Doing so however can be useful in troubleshooting certain issues, such as:

  • Failure to turn on
  • Failure to recognize internal AirPort Extreme card
  • Failure to recognize internal Bluetooth Module
  • Failure to recognize attached devices (Firewire, USB, etc.)
  • Unexpected power off (i.e., sudden unexpected loss of power, not system shutdown)
  • Failure to wake from sleep or unexpected sleep (note this can also be caused by operating system corruption)
  • Failure to recognize keyboard and trackpad
  • Failure to recognize battery
  • Poor battery performance
  • Nonoperational LED Battery indicator

This is due to the fact the SMC may become corrupted over time and not respond properly to certain requests. This sort of corruption can be triggered by a power surge.

SMC Versions[edit]

Shipping Version Latest Version Date Update Released
iMac Early 2006  ? 1.1f5  ?
Mac Mini Early 2006  ? 1.3f4  ?
MacBook Any  ? 1.4f12  ?
MacBook Pro 15-inch  ? 1.2f10  ?
MacBook Pro 17-inch  ? 1.5f10  ?
MacBook Pro Retina 13-inch  ? 2.6f59 10/01/2013
MacBook Pro Retina 15-inch  ? 2.3f35 03/14/2013
Mac Pro 2 or 4 Cores  ? 1.7f10  ?
Mac Pro 8 Cores  ? 1.15f3 08/08/2007

See also[edit]

External links[edit]


  1. ^ Apple general documentation on SMC Updates
  2. ^ Search of SMC Updates on Apple's knowledge base
  3. ^ "Interview with Andy Hall, Product Manager for Oracle VM VirtualBox". 
  4. ^ "Fix screen artifacts on your Hackintosh". Fix screen artifacts on your Hackintosh. Retrieved 17 June 2012. 
  5. ^ " » FakeSMC". Retrieved 17 June 2012.