HP 840 G7 S3 power state support

[simonstar76]

Hello,

I'm facing some issues regarding S0 standby (also known as "Modern Standby") on my HP 840 G7. Specifically, when it enters sleep mode, the current consumption is still very high, and randomly it gets hot as in normal functioning, indicating that there is some background activity that is absolutely not wanted. Even removing the connection (so that "Connected Standby is disabled by policy") doesn't make it better. My powercfg /a reports this:

The following sleep states are available on this system:
Standby (S0 Low Power Idle) Network Disconnected
Hibernate
Fast Startup

The following sleep states are not available on this system:
Standby (S1)
The system firmware does not support this standby state.
This standby state is disabled when S0 low power idle is supported.

Standby (S2)
The system firmware does not support this standby state.
This standby state is disabled when S0 low power idle is supported.

Standby (S3)
This standby state is disabled when S0 low power idle is supported.

Hybrid Sleep
Standby (S3) is not available.

Standby (S0 Low Power Idle) Network Connected
Connectivity in standby is disabled by policy.

So I tried to restore the good old S3 sleep mode by adding and setting the PlaftormAoAcOverride DWORD to 0 under HKLM\Sytem\CurrentControlSet\Control\Power registry key and powercfg /a correctly notifies me that now S3 is enabled (and S0 disabled). With these settings the problem is that the laptop seemingly enters sleep state when instructed but then it is impossible to wake it up (the PC has power because the keyboard lights up when a key is pressed, but pressing a key, touchpad buttons or even a BT mouse doesn't work in waking up the PC).

So the question is: there is a OS/BIOS configuration that allows restoring the S3 low power state on this laptop model?

Thank you