While researching this for myself, I found a solution!
First you can set task manager to start in performance mode any time it is run. With task manager open, click on the sprocket on the bottom left. Then change the "default start page" to "performance". Now every time task manager starts, it starts in performance mode.
Next, add a shortcut to task manager to your startup folder. Create a shortcut to taskmgr.exe and copy it to the startup folder following the instructions below. Cheers!
How to Add Startup Apps (Make App Open at Launch)
- Press Windows Key + R to open the Run box.
- Type
shell:startupand click OK to open the Startup folder. - Locate the application you want to add.
- Drag and drop the app shortcut into the
shell:startupfolder, or right-click the file and select "Create shortcut" and place it there.