Can't see drives on Dell XPS 8940 with fdisk or gdisk to partition them for Slackware

Hello, I'm trying to install Slackware on a new Dell XPS 8940 desktop. Created a boot image usb stick, logged in as root. But my internal hard drives are not visible to fdisk, gdisk, or lsblk. Only the usb stick drive appears as /dev/sda. Trying fdisk /dev/sdb, etc results in a drive not found error.

The Optical drive isn't visible either. However the disks & optical drive are fine in Windows 10.

Bios info:

Bios version 1.0.1 Build 4400.12 UEFI Rom

Drive info:

SATA-0 HDD 6001 GB WD-WX12040N1SV9
SATA-1 HDD 6001 GB WD-WX12D4073KNY
M.2 PCIe SSD 512 GB CD05N905213805V1L

Other Bios settings:

SATA Operation setting -- RAID on

Secure Boot setting -- not enabled

Fastboot setting -- minimal

What is the output of

fdisk -l

What version of Slackware are you using?

^ fdisk doesn't work too well on new hardware. Try gdisk instead.

parted -l

>SATA Operation setting -- RAID on

Do you really want to use RAID mode? Does it work without of it (i.e. plain AHCI)?

What is output of

$ lsblk
$ dmgesg | grep ahci

The problem with the RAID setting is that it requires a special Intel Rapid Storage driver, which is reportedly unavailable for Linux. You need to use AHCI instead, until the kernel provides that driver. If you want to continue using the Windows installation, you need to install the AHCI driver before changing the mode to AHCI, otherwise, the installation cannot start anymore. Additionally, if you intend to access the Windows partitions, you also need to disable Hyperboot.

To my knowledge, it is suggested to use software-based RAID anyway, since hardware-based RAID can prevent the drives from being read if no compatible RAID controller is available, or even if the specific controller used to configure the RAID is not available or functional anymore, since it may contain information about the layout of the data on the disks.

The M.2 SSD should be available as /dev/nvme0n1.

Originally Posted by Abrixas2 it is suggested to use software-based RAID anyway

One small addition: Intel Rapid Storage is semi-hardware RAID.

Real hardware raid is controlled by it's own firmware (some people call it BIOS), so it is transparent for the operation system: you only may need tools to configure it from the operation system, but still you can use firmware to do that.

I agree that in most cases you can use software raid: LVM on Linux (or even ZFS which can also be used as "RAID" in some cases) or "dynamic volumes" on Windows.

Hardware RAID is only good if you run serious server and need high speed (it runs on it's own hardware without touching your CPU) or be OS-independent.

On desktop you better stay with plain AHCI which is supported by Linux.