Rapid Storage Technology
Intel® RST, RAID
1826 Discussions

Raid 5 Broken after switching to AHCI


I have an Intel RST Raid 5 made up with three 6TB drives. I was testing a new NVMe M2 drive and my motherboard was telling me that two SATA ports will be disconnected (SATA5_6) in order to use the new drive. I did that and I could actually test the drive in Windows BUT one of my raid drives was disconnected (because of what I'm mentioning) but still could see all my data. I saw the RST software was complaining about a missing drive but everything was fine.


Afterwards and with this setup, I wanted to test Unraid software and I changed in my BIOS setting the SATA mode from RAID to AHCI. BIG MISTAKE I'm assuming now.. and when saving and exiting the BIOS Windows couldnt get to load, PC restarted like 2 or maybe 3 times until Windows entered in a recovery mode and finally told me it coudlnt repair anything. The moment I saw this I immediately change the SATA mode back to RST RAID and I could finally get Windows to start correctly. 

The problem now is that my raid is showing status failed on the BIOS and on the RST software is telling me status Error (attached image). Apparently one of the drives is not being recognized as part of the array which makes sense as when clicking the exclamation mark drive the serial number appears with a XXXXXXX:0 which doesnt make any sense. I have exported a system info from the RST software (attached too) and I see there is a 7th drive which it doesnt exist (I have only 6 drives connected) and this is the one being used by the array. You can also see the connected drives are

Disco conectado directamente:S2RBNXAH2.....
Disco conectado directamente:WD-WX41D......
Disco conectado directamente:WD-WX31D......
Disco conectado directamente:9VS3X.....
Disco conectado directamente:WD-WXL608.....
Disco conectado directamente:WD-WX61D.....
Disco conectado directamente:D-WX31D....:0

and as you can see the 7th of them is the same as the original but with this weird :0

Im really hoping my data is not lost by this stupid mistake of switching to AHCI and then back to RAID... My idea would be to try to get rid of this weird drive which doesnt exist and make the array have the original drive back into the raid.

I would be very grateful if someone has any clue, really appreciate it
Best regards

The error shown in English would be

Unknown disk on controller unknown, port unknown: missing

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4 Replies

I did find this youtube video which helped me. What was happening is that the partition info of the RAID was lost and I could restore it thanks to this amazing tool TestDisk I follow the steps of the video and on the forum explanation they mention

- Remove RAID

- Create RAID with the same drives in the same SATA ports

- Run the app to detect and restore the partition


Im posting my answer just in case someone else is in this exact situation!

What a relief!


williamfr, Thank you for posting in the Intel® Communities Support.

"What a relief!", Yes indeed, it is great to hear that you were able to fix the problem and now the machine is working properly without losing any data. 

"I changed in my BIOS setting the SATA mode from RAID to AHCI.", Yes, the thing about that is that every time you change the SATA mode in the BIOS, to install the Operating system from scratch will be needed losing all the data unless a back up was created.

"Im posting my answer just in case someone else is in this exact situation!", we really appreciate that, for taking the time to share the solution, we are sure it will be very helpful and useful to all the peers viewing this thread that might have the same scenario.

Any other inquiries, do not hesitate to contact us again.


Albert R.

Intel Customer Support Technician


I'm glad this can help the community. Thanks for the reply Albert! 


williamfr, You are very welcome.

Thank you very much for your response as well.


Albert R.

Intel Customer Support Technician