Q: no boot

Are you following these instructions?

Use Windows 8.1 on your Mac with Boot Camp - Apple Support

What do you mean by "device" in "device can`t find the OSX Partition"?

What model Mini?

What model Mini?

Can you boot to Recovery and reinstall OSX?

OS X: About OS X Recovery - Apple Support

Then from Recovery go to Disk Utility. If the drive shows then format and install OSX.

If it does not show then either the drive failed or the ribbon cable failed.

To start your computer from Recovery, restart your Mac and hold down the Command and R keys at startup.

Hold these keys until the Apple logo appears. After your computer finishes starting up, you should see a desktop with an OS X menu bar and an OS X Utilities window with the options listed above. If you see a login window or your own desktop instead of the Utilities window, it's possible that you didn't press Command-R early enough. Restart your computer and try again.

Choose the option you want to use from the Utilities window or the Utilities menu.

That typically means it can't connect to the internet. Try using an Ethernet cable to connect to internet.

Not all wifi security is supported by internet Recovery see:

OS X: About OS X Recovery - Apple Support

Then see the article and make sure the security y are using on your router is supported.

Do other devices connect to the internet now?