__TOC__== Introduction ==* This application note applies to Airtop3cooling is silent because there are no fans or any other mechanical cooling device* Airtop3 incorporates high power electronic circuits that may emit acoustic noise during operation generally known as "coil whine"* Coil whine is the result of high frequency switching of power circuits that induce piezoelectric force on capacitors and strain on inductors making each vibrate.In some cases these vibrations are in an audible frequency* With Coil whine is common in computers but in most cases it is not audible above the voltage changeslouder fans, which is not the capacitors vibrate from Piezoelectric forces causing them case for Airtop3* Airtop3 hardware is designed using techniques for reducing coil whine, but unfortunately it was not possible to make audible noise.eliminate it completely in hardware* The main source for this noise sources of coil whine are from the the motherboard, graphics card, SSD and power circuits of both supply* Coil whine is often related to the CPU specific workload at a given moment* Adjusting power management policies can significantly reduce coil whine / acoustic noise as detailed below* Worth noting that changing power management settings slightly affects power consumption and internal GPUthermal performance so the user should consider the trade offs.'''It does not affect reliability and warranty.'''== Acoustic Noise Mitigation in BIOS ==# Reboot and press F11 (not DEL) to enter advanced BIOS settings# Advanced --> Setup items availability: Development# Advanced --> Power and performance --> CPU - Power Management Control --> CPU VR Settings --> Acoustic noise Settings:## Acoustic Noise Mitigation: Enabled## Pre Wake Time: 255 ## Ramp Up Time: 255 ## Ramp Down Time: 255 ## For each of the four sections below (IA VR Domain, GT VR Domain, SA VR Domain, VccIn VR Domain):### Disable Fast PKG C State Ramp for xx Domain: TRUE### Slow Slew Rate for GT Domain: Fast/16# Save and Exit
*Disabling C-state should reduce == Reducing graphics related noise from the CPU's power circuit, see below instructionsin Linux Mint ==Symptom:when running Linux Mint using Intel graphics, running glxgears, glmark2 or other graphics intensive application results in continuous buzzing sound1. Activate development setup items of the setup menuSolution: - While in splash screen, # Reboot and press '''[F11]''' (instead of Deletenot DEL) in the keyboard. - Go to ''''enter advanced BIOS settings# Advanced'''' tab --> ''''Setup items availability'''' (first item in : Development# Advanced tab) --> Choose ''''Development''''. Power & Performance - <span style="color-> GT - Power Management Control:#ff0000">'''Caution'''RC6(Render Standby):</span> Now the full setup menu is open, including options that can impair the Airtop3 stability or functionalityDisabled# Disable Turbo GT frequency: Enabled# Save and Exit# Boot into Linux Mint# Open NVIDIA X Server Settings# Select Intel (Power Saving Mode), enter root password to apply# Log off and items that were not checked or don't work.login
2. In 'Advanced' tab == Disabling C-> ''''Power & Performance'''' -> ''''CPU -Power Management Control'''' -> ''''C states'''' -> Choose ''''Disabled''''<br>in BIOS ==3. Back to the tabs menu # Reboot and press F11 (2x '''[Esc]''' buttonnot DEL) -> ''''Save & Exit'''' tab -> ''''Save Changes And Exit'''' -> ''''Yes''''.to enter advanced BIOS settings<br><br>* Using a Discrete GPU should naturally reduce the noise from the internal GPU power circuit but there's also additional configurations that can be done from the development setup menu that may help:1. Enter the development setup menu: # Advanced - While in splash screen, press ['''F11'''].. - Go to ''''Advanced'''' tab -> ''''Setup items availability'''' -> Choose '''': Development''''.2. In ''''# Advanced'''' tab --> ''''Power & Performance'''' --> ''''GT CPU - Power Management Control'''' -> Change the two options below: - ''''RC6(Render Standby)'''' -> ''''Disabled'''' - ''''Disable Turbo GT frequency'''' -> ''''Enabled''''3. Keeping the C-states disabled: - In ''''Advanced'''' tab -> ''''Power & Performance'''' -> ''''CPU -Power Management Control'''' -> ''''C states'''' -> Choose ''''Disabled''''4. Back to the tabs menu (2x ['''ESC'''] button) -> ''''# Save & and Exit'''' tab -> ''''Save Changes And Exit'''' -> ''''Yes''''. [[category: Airtop3]][[category: Application notes]]
