NVME + Optane effectiveness?

My Laptop came with an NVME drive (1TB) with an additional Optane (28 GB) modules a NVME card.
I added a second 1TB NVME drives as laptop had a spare NVME slots - it has no SATA slots.

There is a bios option to specifically switch off the VMD controller but does not seem to do anything else e.g. offer AHCI as an alternative.

I tried to install Linux and it recognised the second NVME drive and obviously has a native IRST driver equivalent but would not recognise the NVME Optane drive.

I looked in bios again, and found I could turn off the optane module and now had three drives - 2 1TB drives and a small 28 GB drive.

I could install Linux on either drive and it booted fine (the existing windows installation was not affected).

I wiped the Linux installations and turned off the vmd controller and tried again - now it would not recognise either drive. It seems my laptop does not have an AHCI mode - I guess it was disabled as I can only add nvme drives using an IRST driver?

It is interesting standard Ubuntu and Mint installers recognise NVMEs but the poxy standard Windows iso does not - I have to add it using dism (or load it at install time).

So now having turned off optane - what performance loss would I get - I could not see any obvious performance loss.

I was really surprised when I did a Macrium Reflect backup with default medium compression - 1 min 50 seconds with optane on, 1 min 40 seconds with optane off.

So far, I cannot see any benefit of having optane on, and at least one negative impact. No wonder it has been decided to abandon it going forward!

Optane can cause so much misery. The fact that Intel abandoned Optane leaving itself with millions of dollars worth of unused inventory should tell you something. Optane proved to be an epic failure for Intel.

As far as I am aware there is no Linux version of the Optane driver, at least not an official one for the consumer grade modules.
Those cache drives can still be useful for an SSD/ NVME based system but it really depends on file access patterns, usage, thier benefit is extremely low latentcy, much lower than even the best NVME.
If you check the Intel forums concerning consumer Optane systems they recommend disabling caching before doing backups.
I was under the impression the RST driver supports AHCI natively as well.
Does Windows not show the controller using AHCI when the RST driver is disabled in BIOS?
It is possible there is a lock in place in the BIOS by the manufacturer to prevent a user 'bricking' the system by switching modes.

DigitalGoat said:

As far as I am aware there is no Linux version of the Optane driver, at least not an official one for the consumer grade modules.
Those cache drives can still be useful for an SSD/ NVME based system but it really depends on file access patterns, usage, thier benefit is extremely low latentcy, much lower than even the best NVME.
If you check the Intel forums concerning consumer Optane systems they recommend disabling caching before doing backups.
I was under the impression the RST driver supports AHCI natively as well.
Does Windows not show the controller using AHCI when the RST driver is disabled in BIOS?
It is possible there is a lock in place in the BIOS by the manufacturer to prevent a user 'bricking' the system by switching modes.

Click to expand...

Thanks - pretty much in line with my thoughts.

Nope - no ahci on my laptop shows. I suspect bios is locked as you say.

Yep - linux would only show drive if optane cache disabled.

I have turned it back on as that is way laptop is intended to be used. Having a tertiary 28 GB drive does not give me any real benefit.

Also, I have never needed to disable optane for Macrium Reflect backups and never had any issue.

Well after messing around, I broke optane and it would not reinitialise. I could see main drive plus a second 28GB module and everything worked ok. However, because of extra drive, I would have to update a number of batch files I use, so I gave up and swapped optane nvme drive for a conventional nvme drive. I see no evidence of performance reduction (I ran passmark and if anything, optane was marginally slowing things down).

Not only that the nominal life of the new nvme is twice that of the optane drive (not that I will live long enough lol).