Compaq 8510w stuck after close/open the lid

[VivienGatineau]

Hello

I have a Compaq 8510w.

It runs Windows XP sp3 (32 bits) and has 3GB of RAM (well 4 but 1 is not used, and I know why). It is configured to do nothing when I close the lid.

And sometimes, when I close the lid and open it again after a while, the computer is stuck:

Display is off, it does not answer to pings, connecting USB devices does not cause the usual "beep", striking keys on the keyboard has no effect.

Some of the buttons (WiFi/BT, sound on/off) seem to work (the corresponding lights are made on/off), but actually nothing can be done but pressing the power button for 4 secongs and re-boot the computer.

I am a computer professional and I know a quite a bit about these things. I know WIndows internal quite well, I understand what a power state is and how device and drivers use power states.

My BIOS is up to date (vF15) and so are my drivers (and I don't think there are specific power drivers for this notebook).

The power settings are made so that nothing is supposed to happen when I close the lid. And sometimes it works as expected.

But often enough to be a real pain, I get this "stuck" issue. This happens randomly, even if it seems to happen more frequently if I leave the notebook closed for "long enough" (sorry, I did not measure the time that it takes).

Any help would be appreciated