Solved For those with new systems having Win 11 preinstalled: Is there still a BIOS option for CSM / legacy mode?

hsehestedt · Oct 24, 2021

I'm working with Tech Support for a company that has a problem with their recovery media. Currently, a workaround to their issue is to enable CSM in the BIOS.

However, now that Win 11 is released, I was curious whether computer manufacturers would get rid of CSM altogether since a Windows 11 requirement is UEFI and CSM / legacy mode would no longer be needed.

If any of you have systems that came preinstalled with Windows 11, could you let me know if your BIOS still has an option to enable CSM / Legacy mode?

zbook · Oct 24, 2021

To upgrade Windows 10 to Windows 11 in the supported fashion the computer must be in UEFI native (without CSM).
The disk drive must be in GPT to upgrade in the supported fashion.

To upgrade Windows 10 to Windows 11 in the unsupported fashion or to clean install Windows 11 the computer can be in any setting.
For example BIOS: UEFI hybrid (with CSM) or Legacy
The disk drive can be MBR.

barman58 · Oct 24, 2021

Not every user will install Windows 11 on new hardware so legacy options will likely still be needed, especially in Industry / Business

I think that in all seriousness, that whether the option is removed or retained depends on the cost of any changes to the manufacturer, will removing the option give an advantage for sales that exceeds the cost of the change, and how may sales will it lose if the option is not there?

I cannot personally see, at this time any advantage to removing the option, though depending on Take-up
of Windows 11 we may see the defaults change to suit the newer OS

We have already seen this with the Bios options on Some ASUS motherboards with regard to default TPM activation changed from Off to On

Fabler2 · Oct 24, 2021

hsehestedt said:
I'm working with Tech Support for a company that has a problem with their recovery media. Currently, a workaround to their issue is to enable CSM in the BIOS.

However, now that Win 11 is released, I was curious whether computer manufacturers would get rid of CSM altogether since a Windows 11 requirement is UEFI and CSM / legacy mode would no longer be needed.

If any of you have systems that came preinstalled with Windows 11, could you let me know if your BIOS still has an option to enable CSM / Legacy mode?

That's a very good question! I would also wonder if secure boot had no option to be disabled?

iko22 · Oct 24, 2021

hsehestedt said:
However, now that Win 11 is released, I was curious whether computer manufacturers would get rid of CSM altogether since a Windows 11 requirement is UEFI and CSM / legacy mode would no longer be needed.

You can still install Linux and Windows 10 in Legacy mode on a Personal Computer, so there is a need for a CSM option.

hsehestedt · Oct 24, 2021

Linux I get, assuming the manufacturer supports it, but there is no need for CSM with Windows 10.

hsehestedt · Oct 24, 2021

Let me clarify my original question, because from the responses it clear that I must have done a poor job the first time.

I am not interested in upgrades. I am not interested in the ability to install other OSes such as Linux or even Win 10.

I am interested only in systems shipping from the factory with Win 11 installed where Win 11 is the only OS that the manufacturer supports. I'm just trying to determine if any of them have simply removed the whole CSM / Legacy support since there is absolutely no need for it with Win 11.

iko22 · Oct 24, 2021

hsehestedt said:
I am interested only in systems shipping from the factory with Win 11 installed where Win 11 is the only OS that the manufacturer supports. I'm just trying to determine if any of them have simply removed the whole CSM / Legacy support since there is absolutely no need for it with Win 11.

Eventually you will be right. Eventually BIOSes will remove the option from the menus. Particularly on budget system builds. With high end custom build, I don't know - could be a different story. Custom or Gaming rigs use high end motherboards in their specification, and these motherboards are not necessarily only built for windows 11 - so they may display such an option even though it is not being used.

I remember not so long ago buying motherboards with an IDE/AHCI option although the idea of IDE disks was way out of fashion. On newer motherboards, that option has completely gone, but it took time for the option to vanish.

Another consideration is that the computer manufacturers like Dell and HP dont actually make the BIOSes or the motherboards. They buy that from the motherboard manufacturers. So, while they may be system building Windows 11 machines right now, there is no sigh that the BIOS providers have followed suit just yet.

So, eventually you will be right. When that time will be, I don't know.

Maybe someone else will chime into this thread with an answer.

Bree · Oct 24, 2021

hsehestedt said:
If any of you have systems that came preinstalled with Windows 11, could you let me know if your BIOS still has an option to enable CSM / Legacy mode?

Removal of legacy CSM support has nothing to do with the version of Windows installed. Since 2020 no new machines would be expected to have CSM support.

Intel said:
Removal of Legacy BIOS Boot Support for Intel Platforms
* Intel is phasing out support for legacy Basic Input/Output System (BIOS) boot mode. Intel products launching in 2020 are validated using Unified Extensible Firmware Interface (UEFI) Class 3 (compatibility support mode removed).

https://www.intel.com/content/dam/s...-Boot-Support-Removal-for-Intel-Platforms.pdf

UEFI machines can have one of the following "classes", which were used to help ease the transition to UEFI. Intel has ended Legacy BIOS in 2020.[83]

Class 0: Legacy BIOS

Class 1: UEFI in CSM-only mode (i.e. no UEFI booting)

Class 2: UEFI with CSM

Class 3: UEFI without CSM

Class 3+: UEFI with Secure Boot Enabled

UEFI - Wikipedia

en.wikipedia.org

hsehestedt · Oct 24, 2021

Bree said:
Removal of legacy CSM support has nothing to do with the version of Windows installed. Since 2020 no new machines would be expected to have CSM support.

Unfortunately, theory and reality are not the same. I have a brand new motherboard that was released this year (2021) which still has CSM as an option.

I also disagree with the assessment that the OS has nothing to do with it. Windows 11 is the first OS that technically supports ONLY UEFI mode although they have made concessions to allow unsupported hardware. Since any technically supported installation of Win 11 has no need for CSM, the logical question was whether any of the OEMs were jettisoning CSM since it is no longer needed.

I had a good reason for trying to find this out, in fact, it may determine the future development of a product that is in development by a major software vendor.

However, I do appreciate the feedback. Thanks!

Ghot · Oct 24, 2021

I'm on the latest BIOS for my motherboard, dated.... 08/12/2021
Note the Boot... items, that become available when CSM is enabled...

I would think that things like these would have an impact on whether motherboard manufacturers keep/remove CSM.

Mark Phelps · Oct 24, 2021

iko22 said:
You can still install Linux and Windows 10 in Legacy mode on a Personal Computer, so there is a need for a CSM option.

Need does not always translate to reality. Recent posts in large numbers on the HP Forums have been from folks who recently bought HP machines hoping to install Linux and discovered no CSM support on these newer machines. So, presuming it will be there because a very small percentage of the PC customer base wants to install Linux is not a valid presumption.

iko22 · Oct 24, 2021

Mark Phelps said:
Need does not always translate to reality. Recent posts in large numbers on the HP Forums have been from folks who recently bought HP machines hoping to install Linux and discovered no CSM support on these newer machines. So, presuming it will be there because a very small percentage of the PC customer base wants to install Linux is not a valid presumption.

Is that on budget machines, high end machines, or on all HP machines? But you are right, need does not always translate to reality.

hsehestedt · Oct 24, 2021

Mark Phelps said:
Need does not always translate to reality. Recent posts in large numbers on the HP Forums have been from folks who recently bought HP machines hoping to install Linux and discovered no CSM support on these newer machines. So, presuming it will be there because a very small percentage of the PC customer base wants to install Linux is not a valid presumption.

Now that was exactly what I was looking for! Now that I know that there are at least some machines that no longer have CSM support I can go back to the company with that info. They are not going to be happy about this!

Thanks for the info.

Dru2 · Oct 24, 2021

Bree said:
Since 2020 no new machines would be expected to have CSM support.

https://www.intel.com/content/dam/s...-Boot-Support-Removal-for-Intel-Platforms.pdf

UEFI - Wikipedia

en.wikipedia.org

Didn't know about this, but I for one applaud it. I've not used legacy anything in years. And I definitely disable CSM as it's the only way to enable Secure Boot (at least on Gigabyte boards).

@hsehestedt, I wish I could answer your question but I've not bought any new PC hardware since 2019. It also would have been good to see your questions answered so to see what's what.

Peace

Ghot · Oct 24, 2021

Sorry about the potato pic, but this is current BIOS settings on my: Asus Pro WS X570-ACE motherboard...
GPT disk with an EFI partition.

zbook · Oct 25, 2021

I'm not aware of any ACP, Windows RE, or PE commands that report whether CSM is available or is / is not in use.

If the BIOS is UEFI and the drive MBR without an EFI partition then CSM is in use.

Finding images of BIOS settings can be extremely challenging.

HP business support has software to view and help end users for any of their computers.

There is / was HP software available to end users that could view and modify the BIOS without booting to the BIOS.
This software starting in 2021 no longer has updates.

Dru2 · Oct 25, 2021

zbook said:
Finding images of BIOS settings can be extremely challenging.

Some desktop boards allow you to capture images of the BIOS/UEFI. Here you install a USB stick and press F12 to capture an image...

glasskuter · Oct 25, 2021

I have a 3 month old Dell Optiplex. Nowhere in uefi bios can I find an option for CSM boot. I can however, turn secure boot on and off.

hsehestedt · Oct 25, 2021

Thank you all for your responses. I now have my answer - there are in fact systems that have now removed the CSM completely.

I suspected this might be the case (which is why I even brought up the question) but I needed confirmation.

For those curious why I wanted to know....

There are a number of programs that use Windows PE or Windows RE based recovery media. Most notably, these include the boot media for backup programs such as Macrium Reflect, Acronis TrueImage, etc. There are many other programs as well, not just backup programs.

Note that when running under Win PE or Win RE you have no option but to run at native screen resolution. So, as an example, if you have a 15 inch 4k laptop screen, your recovery media is forced to run at 4k (3840 x 2160). You have no choice in the matter. In the past, this presented problems for a lot of recovery media because they simply didn't scale well to such high resolution on a small screen. Most manufacturers have solved this, but some have not.

The scaling on some of these is so bad that it is practically impossible to navigate the recovery media. I don't have a screenshot right this moment, but trust me, it's so bad that many graphical elements are simply missing from the screen so navigating the menus is pretty much impossible.

In working with some of these companies, I pointed out that a workaround would be to enable CSM, which would allow the recovery media to run at a lower screen resolution. That was a workable solution, but I pointed out to them months ago that they better fix the problem because it wouldn't be at all surprising if some OEMs decided to dump CSM when Windows 11 was released. It turns out that I was correct. So here we are with some WinPE and WinRE boot media unusable on certain Win 11 systems. I bet they wish that they had listened now. I'm currently working with one company on this issue where I have had an open support case for months, but they are still extremely slow to do anything because employees are still working from home.

In case you are wondering, no, it is NOT Macrium that is affected by this. They scale properly on small high DPI screens