Prevent HP Thunderbolt dock from sleeping

[KlodJ]

My system is a HP ZBook Fury, with a HP G4 Thunderbolt Dock and two HP E243 monitors connected to the dock via Display Port.

When the laptop goes to sleep and is woken back up, Windows forgets which monitor each program was being displayed on and dumps them all onto the main monitor.  Given that I have three monitors (2 external + laptop) and run 4 virtual desktops, this makes a real mess that needs sorting out every time the laptop decides it want to go to sleep. 

[Side note - my old Lenovo system did not have this problem, so its a problem either peculiar to the HP dock or to the way the HP laptop and dock interact]

Does anyone know how to solve this?

My guess is that the dock goes to sleep just before the laptop does.  I say this because I also have a bunch of USB devices connected to the dock and before the laptop sleeps I hear the characteristic sound Windows makes when a USB device is removed.  So I'm guessing that the laptop sees the dock (and hence the monitors) disappear, dumps all programs onto the main screen, then goes to sleep.  (Also explains why my keyboard won't wake up the laptop when connected to the dock)

I wonder if preventing the dock from sleeping would solve my problem. Does anyone know how to prevent the dock sleeping, or if that is even a thing that happens?

I see that other people have had a problem where the monitors connected to the dock don't wake up at all after the laptop goes to sleep.  I don't have that problem, the monitors come back on when I wake up the laptop again. 

EDIT:

I've tried

• Open Device Manager
• Right clock on System Devices->Thunderbolt(TM) Controller - 9A1F,
• Properties->Power Management
• Uncheck "Allow the computer to turn off this device to save power".

I think that's fixed the secondary problem of not being able to wake up the laptop with a keyboard plugged into the dock, but it has not helped with the monitors.