i also diagnose at boot but it passed all the test and reboot

Hello. If the test you used was the PSA or the ePSA tests, those do not test the audio chip so the fact that it passed all the tests does not mean anything about the audio.

If you re-installed Windows and then installed the drivers in the correct order (the main thing is to install the Intel Chipset software before installing the IDT audio driver) and still no audio from either the speakers or headphones, then the hardware has failed.

If you are still under warranty contact tech support for a repair. If you are not under warranty then the workaround is to get an inexpensive usb audio adapter. One of those will allow you to have audio through headphones or external speakers, but not through the laptop's internal speakers.

sometimes when i play videos sound comes from speaker and suddenly its nothing sound comes for 2 to 3 second

If you are still under warranty you should contact tech support before the warranty expires. You might need to have your motherboard replaced.

Destroyers,

I received your PM and will be replying to it shortly.  Thanks for the help Jimco.

TB