Posted under the motherboard section and got no response so I'll try here.

[iPhantasy]

Just installed my new m.2 ssd into my system and as the title says it's not showing up in disk management or device manager. Updated bios and everything. Any ideas would be great.

CPU: i7 5820k

Motherboard: Asus x99-a

M.2 ssd: Samsung 850 EVO M.2

[blackadder]

Shows up in bios? Maybe a bad m.2 slot?

[EIijah]

Does it show up in Bios (You said updated)

[Emanuel_M]

the motherboard has m.2 slot that only supports pcie ssd.

Hi, qazzi and Paul NZ, thank you for your replying, yesterday I had successfully installed the Windows 8.1 Pro x64 into my Samsung SSD using DVD, the followings are what I did, some of those steps maybe unnecessary:

1. I disconnect everything from motherboard except CPU, memory, graphic card and M.2 SSD.

2. In Bios, restore all settings to default.

3. Change SATA mode to IDE in PCH Storage Configuration under Advanced.

4. SATA Support: All Devices

5. Enable CSM and set

Boot Device Control: UEFI and Lagacy OPROM

Boot from Storage Devices: Legacy Only

Boot from Network Devices: Legacy Only

Boot from PCI-E/PCI Expansion Devices: UEFI Driver First

6. Disable Secure Boot (Set to Other OS)

7. Set Booting order: 1st SAMSUNG M.2 SSD, 2nd DVD-ROM

8. Install Windows 8.1, at selecting disk step, at drive option, delete any partition of M.2 SSD.

After all above steps, the warning

Windows cannot be installed to this disk. This computer's hardware may not support booting to this disk. Ensure that the disk's controllers are enabled in the computer's BIOS menu.

Finally disappears

After I installed the Windows 8.1, I connected all hardware back to my machine, changed SATA mode back to AHCI in PCH Storage and re-enable the Secure Boot.

Source:http://www.tomshardware.com/answers/id-2351476/windows-booting-problem-ssd-asus-x99.html

[iPhantasy]

Does it show up in Bios (You said updated)

 

Shows up in bios? Maybe a bad m.2 slot?

Nothing in the bios

[blackadder]

Nothing in the bios

does something disable that m. 2 like a sata port.

[Emanuel_M]

has anyone tried my suggestion?

[EIijah]

Nothing in the bios

Check that m.2 isn't disabled I looked in my bios and by default it was also as blackadder suggested check that the m.2 isn't run off one of your Sata ports (Not sure if that ever happens though)