dalchina, Word Man, and others:

I did a clean install of Windows 10, including manually installing a driver for my integrated video adapter. The sleep problem is still there. Thus, it seems that...

dalchina and others:

Thank you for the advice. I have went out of the frying pan and into the fire.

Some notes:
* I have no USB devices connected other than my mouse
* my machine does not...

Dear dalchina,

That statement yielded this:

The following sleep states are available on this system:

Standby (S3)

Hibernate

dalchina and others:

Many thanks for your pointers. I tried everything (I think) at the various links that you provided. Things that I have tried:

* installed all Windows updates
* used HP...

dalchina: My understanding of 'hybrid sleep' is, with it, the computer performs both sleep (system state to RAM) and hibernation (system state to HDD) simultaneously, with the latter as a backup....

Word Man: Thank you for the advice. I disabled fast startup, and unfortunately this did not resolve the problem.

Also, I disabled hybrid sleep (on a subsequent test), and this did not help....

After an upgrade to Windows 10, my HP Compaq 6005 Pro Small Form Factor will not wake up properly from sleep. After sleep, if I press a key on the keyboard or press the power button, I hear the fan...