IOIteratorNext failed and hardware watchdog in my log file, please help

My mac is painful slow, I did a clean install but the problem continue, I have this log file :

13/05/15 09:17:00,582 com.apple.xpc.launchd[1]: (com.apple.watchdogd) Service only ran for 0 seconds. Pushing respawn out by 10 seconds.

13/05/15 09:17:05,771 watchdogd[617]: [watchdog_daemon] @( wd_watchdog_open) - IOIteratorNext failed (kr=0)

13/05/15 09:17:05,772 watchdogd[617]: [watchdog_daemon] @( wd_daemon_init) - could not initialize the hardware watchdog

13/05/15 09:17:05,772 watchdogd[617]: [watchdog_daemon] @( main) - cannot initialize the watchdog service

Edit1: I am in the safe mode