Why does Dell set the BIOS to RAID always?

I still don't get it why do they set the BIOS to RAID rather than AHCI regardless whether or not the system is running a RAID array or not?

It has always been this way and even on my latest laptop which I just bought (XPS 15 7590) with a single NVMe SSD, it's setup in RAID and even has the RAID app and the Optane shell extensions installed as if it would do me any benefit? or is it just a matter of laziness because they can't be bothered to setup each system depending on what hardware it came with?

Having the setup in RAID rather than AHCI can often lead to some SSDs not working with their manufacturer software (ie. Samsung Magician) or cause problems when you try to install an SSD Firmware update even if it came from Dell, the firmware updater wouldn't even detect the drive(s).

 

I could only venture a guess and say it's because it allows the use of Intel RST drivers which work for the majority of the manufacturers (since most manufacturers outside of Samsung do not provide NVMe drivers)...

 

Just for reference, here are the benchmarks of my 2TB Toshiba NVMe SSD in RAID vs AHCI:

RAID:



AHCI:

 

I've found that Raid typically performs similar to AHCI however I get better battery life with Raid (better idle states) so that's what I've been running.

 

Why you got that low scores from this NVMe drive from Toshiba? From what I can see, AHCI or RAID both isn't where it should be.... https://www.tomshardware.com/news/toshiba-xg5-p-rd500-nvme-ssd,36024.html

Edit. On latest firmware? https://www.dell.com/support/home/u...j&oscode=wt64a&productcode=xps-15-7590-laptop


Toshiba XG5 and XG5-P in the test: BiCS-3 SSDs with few weaknesses review hardwareluxx.de

Possible culprit for the low scores...
Negative aspects of the Toshiba XG5-P 2 TB:

• temperature-related throttling and small SLC cache

 

Have you a doubt that I am not on the latest firmware?

I'll run the test again once I've let it idle for a long time for TRIM Garbage collection

 

Does it mean the latest and greatest has to give best performance? Yeah, I have seen Dell say so in Fixes & Enhancements. After you have checked the performance, run a couple of times with Hwinfo or similar tool to follow up the ssd temps. Atto bench is nice to push it to throttling. And with a nice graph

Crystal DiskMark
ATTO Disk Benchmark

 

which other models of Dell laptops beside the XPS 7590 are the RAID options in the UEFI/BIOS set as the default option? some old Dell laptops either don't have RAID set as default or don't have the RAID option listed at all

 

The 7740 and 7540 I've used recently both had RAID set as the default.

 

My wife's 7 year old Vostro 5470 has it set to RAID as well. I have never seen any Dell laptop setup in AHCI from the factory

 

Mine is set to ACHI from the factory.

 

Every Dell I've bought over the past few years have had RAID as the default. Thinking back, that's been quite a few:
9550, 9560, 9570, 9575, 9365, 9350, 9360, 7390, 7373, 7577, 51m, m17, m15...

 

So here is another comparison of AHCI vs RAID on my Alienware Area-51m:

RAID (Factory Image):



AHCI (Clean Install):



@Papusan @Mr. Fox @tilleroftheearth

Now I'm not sure whether the factory install vs the clean install made any difference but the 4K Random Read/Write speeds which to me matter the most were significantly higher in AHCI

 

RAID has been the default BIOS setting for most Dell products for many years. At least since the XPS M1730/Alienware M17xR2 days. This even includes many laptop models that only had the capacity for installation of a single drive.

Probably something wasn't exactly right with the factory image or the driver version it was using. I've not seen any remarkable differences is drive speeds between RAID (which includes AHCI) and AHCI without RAID when running single drives that are not part of a RAID membership/array. And, you technically should not see much difference since RAID is AHCI with a few extra features added. I have seen some changes in performance that vary with driver versions. Some NVMe drives have controllers that do not function correctly using RAID, so that might come into play as well. It wouldn't be all that surprising for Dell's BIOS default (RAID) to be applied across the board, even when the NVMe drives that are factory installed might not not be intended for use in a RAID configuration. Dell also does some goofy things with HDD and SSD firmware to make otherwise ordinary drives proprietary.

Unfortunately, many people are under the misguided assumption that newer is always better. We know that this is frequently not the case. The best advice is generally, " If it ain't broke, don't fix it" and that is especially true for firmware on systems that block downgrades to older firmware. Upgrading firmware on these systems should be approached with extreme caution and trepidation. You cannot unscramble an egg.

 

Yes my little Insperion 13 7386 all so came set up in RAID, I put in a Samsung 970EVO NVME 1 TB, it seems to run about right 3500/ 2990 I have it split into 3 Data Partitions one of which is my OS. I think I can change it to AHCI but I haven't seen any need to. Samsung Magician is just a waste of time and space.
I have Run My Asus G752VY on RAID and AHCI I didn't see any difference in speed or anything else.
MHO on Dell using IRST driver is because they work for every system pretty much the same less hassle for production and support

 

So I gained another 300 points in AHCI after leaving the system idle post a TRIM command for a couple of hours

 

Always nice to see a few more points. Other than the minor improvement in the benchmark score, was there any practical benefit that you were able to identify? I ask because I cannot remember which of my Windows installations are on NVMe versus SATA SSD. I have to look in Device Manager to figure it out because one doesn't actually feel any faster than the other, even though the NVMe benchmark scores are many times faster. If I pay very close attention during bootup, the SATA SSD might be 1 or 2 seconds faster reaching the desktop with Windows 7, but Windows 10 seems the same on SATA SSD or NVMe.

 

Bootup is around 3 seconds faster

 

Interestingly enough my 7577 which came with a PM961 SSD was set to AHCI when I received it. It was one of the rare instances I've seen a Dell unit not set to "RAID On". I always got in the habit of switching to AHCI mode first before reinstalling the OS without bloat, so that was definitely a surprise. I personally just stick to the default storenvme as I have heard of issues with RST that some people had with DPC latency issues, can't recall fully but I may have had that issue too in a unit a while back.

 

They have no choice. The PM961 does not support RAID. The same has been true of some other OEM Samsung NVMe drives. This is mentioned in this PDF.

http://downloadcenter.samsung.com/c...msung_NVMeDriver_InstallationGuide_Rev3.0.pdf

I am also using the standard Micro$oft drivers. I see no reason or benefit to using proprietary NVMe drivers.

 

Did you purchase it from the outlet? If so the previous owner probably set it to that and Dell just rolled with it. For fun, you could always try loading bios defaults to see what it sets it back to, most likely RAID. RAID mode doesn't mean you're actually running a RAID, just the operating mode. I've had numerous Dell laptops with PM961 and PM951s configured in RAID mode (including my 7577), it doesn't have anything to do with the drive they install.

 

That was my first thought too as it was from Outlet, but Bios defaults also were AHCI. I just don’t use RST due to DPC issues some laptops had like 5-6 years ago, maybe it’s different now but I like to keep things simple so I stick to MS default storenvme.

 

If you do any large Data transfers you will see quite a difference between SATA and NVME Especially with top-end SSD's
Spartans Benchmark looks very slow for NVME M.2 4 lane mine gets 3500/3000 Dell Inspiron 7386 Samsung 1TB 970 Evo. Even my G752VY with Samsung 512GB 960 Pro m.2 NVME 4 lane get 2900/2500. I can move 100GB batch files in just a couple of minutes from the computer to USB NVME external case. Very fast transfers Full version movies in seconds. Not all m.2 SSD are equal and SATA is limited to 500 GBs or so by the controller.
With all this said everyday use for the average user, it's hard to tell the difference between a 500GBs SATA SSD and 3500GBs NVME SSD, its when you actually use the full power that you see the difference.

This is all a miracle to me I remember it taking overnight or longer to Render a Cad drawing after making changes. The same drawing now happen in seconds.

I agree with my Asus G752VY that came with a 256GB 961 or 951 running in RAID mode. The first thing I did was drop in the 512GB 850 Pro I stayed in RAID mode for a year or so. Then switch to AHCI just to see if there was any difference. I did not notice any difference at all. My Dell is still in RAID mode

 

Don't compare SK hynix PC400 512 GB with the better NVMe models. Its a cheap drive with not the best specs. And it perform really bad in many notebooks.

 

I didn't think I did, I was pointing out that his SSD was very slow for NVME. I'm quite aware of Hynix 512gB as my Dell came with on it now a D: in my Insprion with a 970 as C:-F:-G: Don't ask about why I have so many partitions I use them for business