I have had this "Computer enters Power Saving Mode" nagging problem for years.
Each time I manage to solve it, pass it or reduce it, I forget about these forums and people trying to solve, so this time I wanted to comeback with the way I have... apparently solved it this time.
You are not alone. But no one cares for your screams.
Description of the problem. Computers of several brands, makes, and models and during multiple different uses, has the monitor entering the dreadful "Entering Power Saving Mode".
Severity During different rashes, yes its seems to happen in rashes, because it behaves erratically, which can make you crazy trying to figure out what is the issue, sometimes it's solved with a restart, sometimes nothing seems to help, you have to retry starting up up to 50 times, for that one quick time when Windows enters and you quickly make all the config changes that you saw on the last youtube video of possible fixes.
This past week, it was so severe for me that I was thinking on getting a whole new system. It happened right after the Alienware logo and before Windows first screen.
Hypothesis of causes I am not an expert and dont pretend to pass as one, and as I write I am waiting for the computer to fail. Its horrendous.
I beleive that this is a problem that is triggered by different causes, seems to me to be related to causes related to energy and heat. Sometimes the computer thinks it's too hot, and to prevent damage triggers this behavior. Other times the computer has a problem with too low energy.
Nos the problem is -and I am sorry to say this- because many will wish it was easier. It's a problem between the graphic card and the operative system.
However all are fine... the card is fine, the PC is fine and the Windows is fine. But there is this -this is why I call it a behavior- where the computer triggers the Power Saving Mode.
Experts will tell you this: -Clean your computer, it is dust
-Change and ventilate it better, its heat
-Change the Sleep and Hibernate configurations
-Update all your software, including and especially BIOS and graphic card
-Change your CMOS battery
-If your computer has more than one Video Card, disable one of them
What has worked for me -Updating BIOS
-Restarting the CMOS battery
-replacing the CMOS battery
-And always update, reinstall your BIOS drivers
Also maintain and do a clean reinstall of your Graphic Card.
This time... and I HOPE this keeps working... It was the CMOS battery AND updating from the manufacturer website.... this is important, all my software said I had the most recent drivers... but it was wrong... some had updates and I reinstalled several of them.
Man I hope this helps you and you find the solution for your particular version of this monstrosity.
You can find scores of pages of people suffering it, but all the manufacturers involved they deny it and clean their hands... because their equipment is ok.
But Windows, Graphic card and the least guilty of them, Your PC manufacturer or Monitor Manufacturer are the least guilty ones.
I also forgot, many experts will tell you to check your cables, nap...