Windows 10: Dell Latitude. Can't Clean-Install because of "AHCI" and "RAID" complications.

I'm trying to Clean-Install Windows 11 onto my laptop. Apparently, there's some obstacle that prevents certain laptops--like this Dell Latitude 7430--from Clean-Installing, something to do with "AHCI" and "RAID" modes in the BIOS. According to this thread on the Dell forum, one way around it is to switch from "RAID" mode to "AHCI" mode in the BIOS-settings, as the picture just below shows:this will then allow the laptop to at least Factory-Reset. However, according to "JohnSnow"s comment in that same thread--see the next inserted picture--this way doesn't allow for a Clean-Install but rather

:)

 

How to reinstall windows 10 and have AHCI mode enabled with it?

All steps on your PDF seem to be OK. When you have click 'Apply Changes' in Step 4 and go back to first screen in step 3 is it showing AHCI or RAID? If it's showing AHCI you should be able to do a clean install.

My screenshot from Device manager is taken after I change RAID to AHCI and did clean install of Windows.

@Dave

>"there is no way SATA Mode should be set to RAID, if there is no drive mirroring"

As I already said Dell use RAID mode most of (all?) their new devices as default even with devices that have only one disk. This required Intel RST drivers to be used while doing clean install.

Within last year I have make that RAID to AHCI conversion to few different brand new Dell laptos.

 

Failed AHCI change from RAID on Dell 5500, w10p 1909,

Followed this tutorial -
Enable AHCI in Windows 8 and Windows 10 after Installation
Printed it and did it carefully step-by-step. Found each and every bit in registry.

Reason is to get a Linux distro to see the WinOS and others(penguins) have found that many Dell laptops are not set to AHCI.
Previous bios settings were RAID (never changed by me) - this was the third of 3 options - Disabled, AHCI, RAID.
After following steps in tutorial made the change from RAID to AHCI in Bios (made no other changes).

Machine failed to restart into Windows, repeated boot loops (as far as I could tell) and the Dell SupportAssist muscled in twice trying to get a download of a complete image - cancelled by me).
Eventually Windows presented a blue recovery box with "Restart" or "Advanced options".
Tried both .. only ever choosing restart within advanced though.
Repeated fails.

Went back to BIOS and reverted to RAID = success and back into w10p.
All I want to achieve is for Linux to "see" Windows folders/files just like the old days with w7p .... ahhh, those were the days.

Machine = Dell 2019 version Latitude 5500, i5 8th gen, 16GB ram, 256 nvme ssd with w10p 1909 build (up-to-date), storage microSD in slot (no boot or OS on it), nothing else connected/plugged in.

EDIT:
Checked regedit for those values and found these...
...Services\iaStorV = start still set to '0' value data
...Services\iaStorAVC\StartOverride = Value Name is '1' not '0' and value data is '3'
...Services\storahci = Start still set to '0' value data
...Services\storahci\StartOverride = Value Name is '1' not '0' and value data is '3'
Paul

 

Switch from Raid to AHCI

That may depend on the system (hardware and drivers).

On my Dell Latitude e6230, repeated CrystalDiskMark speed tests on my 500GB Evo 860 done before switching from RAID, in AHCI mode (default MS driver), and after switching back to RAID showed:

Sequential read/write speeds 0.4%/1.3% slower in RAID mode
Random 512KB read/write speeds 0.3%/0.3% slower in RAID mode
These differences are within measurement error, since individual runs in a given mode varied by much more than that.

However, when it came to 4KB random read/writes, things were reversed
for QD=1, the RAID mode was 8.3%/4.5% faster
For QD=32, the RAID mode was 3.6%/12% faster
Most of those figures are larger than the min/max difference between runs within a given mode, which suggests the RAID mode may have some small edge over the AHCI one (possibly driver-related), though it could still be down to chance.

So, unless there's some other need to switch, it may not be worth bothering, and if small performance gains are of interest, it's probably worth doing before/after tests with one or more piece of benchmarking software.

If doing that, it's probably worth leaving things to quieten down for a while before benchmarking, as for some reason, after the switch to and back from AHCI, various system processes (search indexing, etc) seemed to dribble along in the background making disk accesses for some time before the system got nicely idle.