Check OSX Installation

[Fed10]

Hello,
some months ago I have installed El Capitan, in dual boot with win10 on my SSD 850Evo 500GB, and after I have updated it successfully to High Sierra.
After that, I've re-installed Windows on my computer, being careful not to touch the OSX Partition.
In Disk management, 250GB are unavailable, so I think OSX is installed yet, but I've tried several option in the bios, without success.
Is there a way to fix the boot, like bootrepair for grub, or check if OSX has any problem, or check if the bios settings were changed to the default ones?

Regards.

 

[vulgo]

In Disk management, 250GB are unavailable

Does Disk Management label the 250GB as 'Unallocated' or 'Healthy' or something else, I don't see 'Unavailable' anywhere in my own partitions.

but I've tried several option in the bios, without success

What are you trying to do? Boot Clover? UEFI or Legacy?

 

[Fed10]

Thank you for your reply.
250GB are Healthy.

I'm trying to boot clover (firstly installed on my first ssd, I think/hope) but there isn't boot option, except for one drive that is a backup drive, where there's installed the windows boot.

From my bios (Asrock H170 Pro4s) I don't understand how I can discriminate between UEFI or Legacy, but I've disabled "Secure Boot".

Since I want to add an SSD (850Evo 250Gb for Hackintosh and 850Evo 500Gb for Windows and Games) I think it is better to start from zero, right? I've to install firstly Os X and after the dualboot with Windows, right?

EDIT: I've found the USB Drive I used for the first installation and Clover boots. Can I start from here following an how-to?

Thanks!

 

[Fed10]

The boot is Legacy, but I don't see any of this choice in the boot!