Having this issue go on sometimes. Sometimes after a reboot it doesn't show up but sometimes it does.  May 29 21:39:23 Tower kernel: i801_smbus 0000:00:1f.3: SMBus is busy, can't use it! May 29 21:41:54 Tower kernel: i801_smbus 0000:00:1f.3: Timeout waiting for interrupt! May 29 21:41:54 Tower kernel: i801_smbus 0000:00:1f.3: Transaction timeout May 29 21:41:54 Tower kernel: i801_smbus 0000:00:1f.3: Failed terminating the transaction May 29 21:41:54 Tower kernel: i801_smbus 0000:00:1f