Hmmm
Do you mean that it won't stay sleeping, and keeps waking itself up for no apparent reason?
If the answer is yes, I suffered from that too. I was running HTPC on Windows 7.
Out of pure frustration, and because nothing else runs on that PC, I installed the 'free' Windows 10 upgrade over the top.
That cured it, but I now have other issues to resolve, namely the 'Start' button doesn't work, and neither does my shortcut that terminates a remote desktop session, leaving the HTPC showing theater view rather than a logon screen.
I am none the wiser as to why the HTPC kept waking up on Windows 7. I would rather go back to Windows 7, so will watch this thread with interest.
If the answer to my question is "No", you will need to explain what you mean in more detail...
regards,
-marko