If the issue hasn't been resolved I have two guesses.
1. Check to see if you have Dell SupportAssist, if you do, disable this hog! It's the most likely culprit in my opinion. Run it manually when you need it. Disable below.
2. You have something running at startup that is causing this issue. Go to Task Manager, select Startup tab, any programs listed that you don't use on a daily basis, right click on the program and select Disable. Example, you may find Cortana, if you don't use it, disable it. They may be a couple programs that you'll want to startup, but most are not required. You can always startup the program manually later as well. As an example, I have 18 startup programs, but I only allow 5. I don't need iTunes, Amazon, Steam, Xbox Services, etc. most days. Reboot after you've disabled. If you don't know which ones you can disable, just lets us know, we'll help.
There are services that you can set to Manual as well, but this can cause other issues.