the hour glass

?
Are you running anything special? How long ago did it start and did you install anything specific just before it started?
 
Check your task manager and see if there's not something using up a lot of memory or processing power . Do you see the light from your hard drive flash a lot too ( indicating drive activity )? If you have very little space left on your disk you can see bad performance too

Hi brasileiro
 
Welcome to the Community Forums.
 
That suggest to me that you have a process in background that is try to run every 15 seconds or so...has this been happening for a while or has it just started? Also, have you tried rebooting your system to see if it is just a temporary occurrence?
 
Regards, Baldrick

started 01/11/16

OK, I know that it is a while back but can you by any chance remember as to whether you installed some new software / application on or just before that date?  And if so then could you try uninstalling it to see if it resolves the issue?
 
Baldrick