Inspiron 7490 BIOS: How to turn off intel 'RAID on', and swith disk mode to AHCI?

So, it seems that the only reasonable way to 'make life much easier for hundreds of people' is to push Dell to release new BOIS with AHCI supporting inside.  But unfortunately, we still haven't gotten any valuable feedback from Dell. 

Hello,

I'm french and my english is very poor, excuse me.

I have the same problem on my laptop but it's a gift for my birstday, I cannot change it. This computer is very beautiful but I'm really frustrated that I cannot install Linux on it.

I hope that Dell will do the job to activate AHCI in the BIOS and give us a solution. It's Christmas

Hello, 

One more user concerned... I got this wonderful machine for Xmas (bought it during black Friday... waited a while for it!) and as soon as it was unpacked, tried to install my favorite Linux distro...

Tried and tried again but nothing works, including installing on an SDcard and then trying to access the nvme disk with mdadm! 

I use Dell's products for a while, but I am seriously considering returning this one and go for another brand/model.

Good luck with this machine and it's buggy bios

Dear friends,

Unfortunately, I haven't found a workaround, but would like to leave my footprints.

For those who cannot boot with LiveUSB of ubuntu 19.10 & ubuntu 18.04 LTS, 
add nomodeset and modprobe.blacklist=intel_lpss_pci to grub loader options.
The only problem will be a touchpad driver after booting.

With my very limited knowledge, the reason why Linux cannot find your SSD is the BIOS remap its device address.

[    1.125977] ahci 0000:00:17.0: Found 1 remapped NVMe devices.
[    1.126969] ahci 0000:00:17.0: Switch your BIOS from RAID to AHCI mode to use them.

Some persons worked to develop the patch, which I haven't tried.
[v2,1/5] ahci: Discover Intel remapped NVMe devices - Patchwork 

If it is the case caused by Intel SSD driver, replacing original SSD to another SSD might work??

Same problem here, 2 months that I try to install a Linux OS, but without AHCI mode it's impossible...

Dell used to be known for not having to worry about these kinds of details. Not anymore.

And, at the price of the device I estimate that the support of at least one Linux OS is normal, or at least should be possible.

To give you an idea of the number of people affected :

https://askubuntu.com/questions/1181726/no-hard-drive-detected-during-ubuntu-19-04-installation

https://askubuntu.com/questions/1180881/i-dont-see-ssd-in-ubuntu-install-on-dell-latitude-7400-with-...

https://forum.ubuntu-fr.org/viewtopic.php?id=2046969

https://forum.ubuntu-fr.org/viewtopic.php?id=2044309

https://www.dell.com/community/Inspiron/SSD-NVME-non-reconnu-lors-de-l-installation-DELL-7490-Ubuntu...

https://forums.linuxmint.com/viewtopic.php?t=306195

https://www.reddit.com/r/linux4noobs/comments/e9zln4/linux_install_directly_to_nvme_ssd/

https://bbs.archlinux.org/viewtopic.php?id=251090

https://www.dell.com/community/Inspiron/Not-able-to-set-SATA-operation-to-AHCI-in-BIOS-Inspiron-7490

...

There's tons of subjects about this problem if you look hard enough, so at some point Dell might want to do something.

Sincerely

Year2020 arrived, when can we get the BIOS FW with AHCI supporting?

Found this thread while trying to install Ubuntu on an Inspiron 5500 series I bought in December with raid enabled. Based on this thread and lots of others, it’s not possible without kernel changes and that got shut down 6+ months ago.  See the end of this thread, referenced earlier: https://lore.kernel.org/linux-pci/20190620061038.GA20564@lst.de/T/#rb97cf0289a450130870fdf177bf55e9c146d250b

I am lucky and my BIOS allows AHCI mode so it seems it should be do-able for the 7500 series, if Dell chooses. 

Hello,

I bought this computer in december from Dell obviously because Dell was known to have good compliance with Linux and specifically Ubuntu.

This limitation from the BIOS is really a shame. Why the hell don't you warn the buyer "hey guys, don't buy this, because its a windows only thing..."

You cant even boot any proper tool of your choice in order to make a backup, and I imagine bad issues if i later need to change things in my SSD configuration...

I had many computers (pc, mac, servers, embedded devices) in my life for professional or private use, I never had such limitations moreover for a ~1300€ laptop. We are not talking about a 30$ Raspberry Pi.

Please assume your position of "linux/ubuntu supporting vendor" and just work on a BIOS/Firmware that is supporting AHCI mode or provide the necessary drivers.

I hope it was not a deliberated choice from Dell to make such a limitation and that you will provide a workaround.

Thank you for your help and taking care of this situation.

Hugo

Same here, I too bought this laptop as I know Dell's history of support Linux but that "problem" is totally stupid... I infact know that Lenovo has had a laptop with the same "feature" and after some time patched it out. So please Dell do the same here, but not wait for years as I and presumably a lot of other people will sell this laptop if this won't be adressed in any way. This problem is just laughable, the only reason I see Dell doing this is that they got some money from Intel or sth like that...  

Maybe there is another way tho as with older models you could set BIOS settings like Dvmt and other ones with a patched grub (setup_vars https://github.com/datasone/grub-mod-setup_var) that would otherwise be inaccessible! I already extracted the vars with the universal IFR extractor. If someone can support me here, we might get this working without Dell. 

https://paste.gg/p/anonymous/1b29913a63ff41f586b6eb1523aa5463

0x78394 QuestionId: 0x415 equals value 0x0 {12 06 15 04 00 00}
0x7839A One Of: SATA Mode Selection, VarStoreInfo (VarOffset/VarName): 0x44, VarStore: 0x5, QuestionId: 0x416, Size: 1, Min: 0x0, Max 0x1, Step: 0x0 {05 91 7C 0B 7D 0B 16 04 05 00 44 00 10 10 00 01 00}
0x783AB One Of Option: AHCI, Value (8 bit): 0x0 (default) {09 07 7E 0B 30 00 00}
0x783B2 Suppress If {0A 82}
0x783B4 QuestionId: 0xB7E equals value 0x0 {12 86 7E 0B 00 00}
0x783BA QuestionId: 0xB47 equals value 0x0 {12 06 47 0B 00 00}
0x783C0 And {15 02}
0x783C2 End {29 02}
0x783C4 One Of Option: RAID, Value (8 bit): 0x1 {09 07 7F 0B 00 00 01}
0x783CB End If {29 02}
0x783CD End One Of {29 02}

That might be the right var but does it need to be 0x0? But that's the default value, why doesn't a BIOS reset fix it then? Anyone?

EDIT: 

AHCI really seems to be in the BIOS so there is no reason for it to be disabled!

BIOS version 1.4.1, released on the 31/3/2020, still does not have an AHCI option.

Also, to complete my previous post I tested the last BIOS update and It doesnt make the ahci option available.

I read some documentation about NVME and as far as as I understood, the nvme standard is supported by linux since many years (even on BSD). The problem here would be to simply disable the Intel raid layer that is useless on a single-drive computer.

Scientists made standards and norms, brands like Dell make it not compliant !

Can someone @ Dell answer about this point ? You are losing clients !

I agree, they have lost me. I will return and never buy another Dell product

Hey guys May 1st update, someone's succesfully installed linux on his system. You can all do it too. There's a Linux distro that supports install with Raid on. So if you don't care about the distro, then go to Endless OS, make a USB stick and should be quick and easy.

If you're like me and wish you had ubuntu, then here's the link to the guy's post. There's a bunch of instructions but difficult to follow unless you're a guru. So anyone who actually succeeds in building an ubuntu image or does an install like the guy did there, then please post detailed instructions. Some parts of the instructions are not that detailed so not so easy for regulr people. Here: https://askubuntu.com/a/1232818/208345