Win 8.1 Won't Stay Asleep

I have an old desktop HP Pavilion It runs 8.1 and I use Chrome. When I'm not using it I put it to sleep (mostly at night.) It's been waking up. Last night it honestly woke up about 10 times. It's been getting worse and worse. Under the "last wake" command it only shows USB. I've check the drivers and all is well. My virus program (AVIRA), & malware program (Super-anti-SpyWear), are set to do updates manually. (I've turned off Windows virus stuff.) I've had these two programs for awhile so they aren't the cause. I'm on the other side of the room so I see & hear the computer go on. All I use is a backup program that faithfully runs at 3 am twice a week. That's all that should wake.
Thanks for any help. Dawn

 

Open Device Manager > Human Interface Devices.
Check the Power Management tab of every device - it should look like this.


Do the same for Universal Serial Bus Controllers.

 

Thank you. I did all the stuff other than the USBs when I recently wanted to make sure I had good drivers. Some of what you mention said to Turn off to save power. I'll check again with USBs but it looks like some don't have a power management choice. I'll go there now.

 

Both boxes in the posted image should be unchecked.
Ignore the devices without a Power Management option.

 

Why don't you just switch it off... then back on when you want to use it?

 

Once again I have issues here. I'm trying to answer the posts in the order they came in but it's causing me to answer both. You say "both boxes in the posted image... " I see more than one box when I open a USB. I have a couple of theories about what you are suggesting but I'd like your help to spell it out. What am I missing? It turns off when the power option tells it to. So it's on for 5 mins & then goes back to sleep. Thank you for the assistance.
It's a desktop & I have to put it in my bedroom. I have it set to come out of sleep at 3 am twice a week to back up the computer to an external drive. The backup won't work if it's switched off. Also, when it's shut down it takes forever to start up. The monitor goes through all kinds of tests (thanks HP.) I've been told that if you have an older computer (& a new monitor) it's better to put it on sleep. For a number of reasons I'd like to solve this puzzle. Something is obviously going wrong.
When I was young and 1st started driving a car I'd turn the radio up if I heard signs of a car problem. I didn't want to address the car noise. Now I do the opposite (I took a car repair class.) I want the answer if anyone is able to provide one. I sincerely appreciate people who can help.

 

Work through this.
https://www.ghacks.net/2015/01/10/prevent-your-pc-from-waking-up-automatically/

 

I just came back because I discovered something simple. If you do a -last wake- command or the like (it's very easy to find a simple command that tells you what woke your computer. I don't have it in front of me.) I kept getting a USB at the beginning of the results. I couldn't read the rest (as you can see above.) I wasn't computer savvy enough to handle the link above. So, once I knew it was a USB device I unplugged one every night until the computer stopped waking. Even though Power Management said it was set correctly, it was the Mouse. Why and how is beyond me. I got a cordless mouse after I cleaned out everything that I could find that would be associated with the old mouse. Presto.