Debian installer does not show partitions on my disk.

[Gaëtan Herfray <gaetan.hfy@gmail.com>]

Hello,

I'm trying to install Debian on my laptop (Asus N550JV) with Dual-Boot with
Windows 8.1. I have tried those two options:

1/ Install Windows 8.1, then install Debian. In that case, I can find my SSD
hard drive in Debian, but it is not showing my partitions. (it is only showing
free space)

2/ Use a live CD to create a partition with cfdisk which I format in ext4 with:
mkfs -v -t ext4 /dev/sdax and then try to find the partition in Debian
installation, but still can't find it.

3/ Install Debian on that disk anyway (and then remove Windows), but after
installing debian, I cannot find my hard drive in the boot options of the BIOS.
So I cannot boot from any OS.

Informations :
 - Compatibility Support Module (CSM) is enabled in my Bios
 - Secure Boot is disabled
 - I am absolutely sure that my partitions exists (because I start Windows if
 I remove the CD and have no other hard drive or USB on my computer)

May you know why I encounter those issues ?

Thanks a lot.

Best regards.