Kernel panics shutting down imac

[allisonv7]

Out of the blue yesterday my computer started randomly freezing. Sometimes it works fine for a bit, other times it freezes a minute after startup, any ideas??



Sep 13 13:33:55 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 13 13:38:29 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 13 13:47:39 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 13 13:54:29 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 01:53:33 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 01:58:50 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 02:02:33 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 02:08:42 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 02:38:40 localhost kernel[0]: AppleSMU -- shutdown cause = -110
Sep 14 02:45:36 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 02:53:17 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 03:41:22 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 13:45:16 localhost kernel[0]: AppleSMU -- shutdown cause = 3
Sep 14 13:50:03 localhost kernel[0]: AppleSMU -- shutdown cause = 3

[Doctor Q]

Your first step should be to read our Kernel panic guide and see if the causes and cures described there apply to you.

Also, please tell us what iMac model you have and what O.S. version, since it may matter.