i found out what's keep waking up my machine

[zassou]

my computer had a habit of randomly waking up from sleep. im a shallow sleeper and i live in a quiet place, so a sudden kick off of my fans usually startles me.

 

ive been investigating this (seemingly) paranomal phenomenon for years and until this day, i thought it was those sort of things which:

• you have no idea why it happened
• you can't repeatly reproduce it since it seemly happens randomly
• there's another solution for this (by power the pc off) so it doesnt need to treat the symptom

so far i have been ruled out software factors:

• my mobo's wake up on lan setting is, and has been off
• and boot when power is also off. again, not a server, dont need it.
• it's not the googled answer, i tried it. not working. windows update won't wake my pc

 

so yesterday i was slouching on my bed after waking up, watching vids with my phone, and this happened:

firstly, on of my monitors cycles power, briefly shows no signal and go to power save message. (i use dp therefore im not turn them off for compatible reasons)

seconds later, my rig woke up. this caught my attention. i loged on, and put it back to sleep, and keep wating. altho i fell asleep later.

 

then that monitor flashes again, followed by full speed fan spinning by my pc's waking. then i find out what the culprit is.

this is what my situation:

• i have 3 dell u2414h monitors. i daisy chained the left to the right. (aka MST, multi-stream transport)
  • so there are two ports from the graphics card, one for the centre, one for right and left.
• i bought those monitors in different times and therefore probably in different revisions.
  • the left and right monitors dont have their power leds pulsing when in standby mode, so i only turn off my main monitor which is the earliest one.
  • the only thing in the monitor menu is whether or not keep led on while monitor is on. not in standby.
• the u2414h has a usb 3.0 hub, via a type b to a cable to the computer.
  • the hub is powered by monitor itself, meaning it wont work if the monitor is off.
  • i plug various usb devices to the monitor to reduce cable clutter; and kb/m directly to mobo for compatible reason.
  • i have devices pluggin the middle and right monitor.
• my keyboard can't the machine, i know some can but mine can't. nor it has a power button
  • mouse click however, does wakes the machine, not movement tho.
  • i dont believe xbox controller can wake the pc like you can wake xbox by pressing the guide button.
    • the guide button dont get recognised by any game at all other than steam itself

this is my deduction:

∵ i only turn off the middle monitor as it's the only one has a pulsting led during standby

∵ i have usb device pluggin the right monitors, but non of those devices can wake a pc (controllers, audio, storage)

∵ this monitor power cycles

∴ when this monitor power cycles, the built-in usb hub wakes up the pc.

 

Q.E.D

 

diagram:

Spoiler

 

left to right: DP in, mini DP in, DP out(daisy chain), HDMI in x2, audio out, USB 3.0 type B, USB 3.0 type A x3

(another usb3.0 port not visible)

 

 

[Bombastinator]

Could be.  I had a similar problem but it turned out to be my cat.