Question How to reinstall Windows 10 (clean) without creating additonal partitions?

Endre

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When I installed Windows 10 on my Samsung 970 EVO Plus 250GB, I wanted this whole M.2 SSD to be a single partition: “C”
But Windows 10 creates 3 other additional partitions for system etc.

In the Windows XP era this didn’t happen...

QUESTION:
Is there a way to avoid creating 4 partitions, instead of just 1?
(I’ve seen no other option when installing)
 

britechguy

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Because in the XP era a number of recovery options that exist now didn't then.

Those additional partitions are generally very small in size and, believe me, there can be occasions where you want them. Unless you are desperate for space keep 'em.
 
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Endre

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Colif

Win 11 Master
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if you change the bios to legacy boot method and then run win 10 installer, delete all the partitions as usual, then let it create its 4... you can then delete all 4 and create 1 and win 10 will install itself all into that 1 partition. That is how I did mine the 1st time I installed win 10 (a version update later made the recovery partition)

MTE7LGg.jpg


If you leave boot as is, you will need to have at least 2 partitions, you need a System (EFI) and C drive. the other 2 small partitions are less necessary for windows to work, though recovery partition is likely to be remade when you get the next version update

vqBDIvN.jpg


One of the 2 extra partitions (as you put it) is the boot partition and unless win 10 installed as legacy, PC won't be able to boot without them. The partitions are tiny really
Recovery partition - 500mb
EFI partition - 100mb
OEM partition - 900mb.
C Drive - takes the difference

On a 2tb hdd, you not going to miss that amount of space really. If you set it up as legacy boot method, you could create 2 partitions and point windows at 1st one as C but windows will still create the recovery partition when you get the next version update in 6 months.
 
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Endre

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if you change the bios to legacy boot method and then run win 10 installer, delete all the partitions as usual, then let it create its 4... you can then delete all 4 and create 1 and win 10 will install itself all into that 1 partition. That is how I did mine the 1st time I installed win 10 (a version update later made the recovery partition)

MTE7LGg.jpg


If you leave boot as is, you will need to have at least 2 partitions, you need a System (EFI) and C drive. the other 2 small partitions are less necessary for windows to work, though recovery partition is likely to be remade when you get the next version update

vqBDIvN.jpg


One of the 2 extra partitions (as you put it) is the boot partition and unless win 10 installed as legacy, PC won't be able to boot without them. The partitions are tiny really
Recovery partition - 500mb
EFI partition - 100mb
OEM partition - 900mb.
C Drive - takes the difference

On a 2tb hdd, you not going to miss that amount of space really. If you set it up as legacy boot method, you could create 2 partitions and point windows at 1st one as C but windows will still create the recovery partition when you get the next version update in 6 months.

Thank you!
The “legacy boot” is an interesting subject. I’ll study to see if I can enable that on my Gigabyte Z390 Aorus Master motherboard.
 

Colif

Win 11 Master
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Moitherboard should support both still as not all operating systems support GPT yet.

its on the bios tab in Advanced view, under CSM support. it appears the default setting is enabled, it supports both but win 10 might still insist on UEFI snce default supports both. I can't see a way to just set it to legacy

page 59 of manual - http://download.gigabyte.us/FileList/Manual/mb_manual_z390-aorus-master_1001_190219_e.pdf

have a look in the Windows 8/10 features menu, manual doesn't spell out the options in there.
 
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Endre

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Moitherboard should support both still as not all operating systems support GPT yet.

its on the bios tab in Advanced view, under CSM support. it appears the default setting is enabled, it supports both but win 10 might still insist on UEFI snce default supports both. I can't see a way to just set it to legacy

page 59 of manual - http://download.gigabyte.us/FileList/Manual/mb_manual_z390-aorus-master_1001_190219_e.pdf

have a look in the Windows 8/10 features menu, manual doesn't spell out the options in there.

Unfortunately I tried every option listed at page 59, I’ve put everything on “Legacy”, also a few tweaks in the “Favorites” tab, but I couldn’t make it work.
And nobody else, out there, put a video on how to do it for Z390 Aorus motherboards.
Tutorials made for other motherboards are good, but they don’t apply to mine.
 

Colif

Win 11 Master
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it appears to me that you have no choice.

As brittechguy pointed out, the 3 extra partitions are not very big, the most you will lose is 600mb (maybe - see last sentence) which on a 2tb drive, is nothing at all.

Recovery partition is used for when/if you need to boot PC into advanced startup, which is useful for all sorts of things. Also used for resets. (499mb)
EFI partition is necessary as its the boot partition (100mb)
C: - obvious what this is.

OEM partition -this is created after a windows version update and contains the files currently in the windows.old folder (windows.old is the contents of the previous version of win 10 in case you need to roll back to it). This may not be created during install process **

Even if you could only have C & D on the drive, the next version update (due in 6 months) will create the OEM partition.

I would just let windows create the partitions it needs, and then after that stage, during installation, you can resize C drive and create D.

**There might be another partition created as starting from Version 1903, Windows now saves 16gb of space for future updates. I don't know if this is included in the OEM partition, as it only applies to clean installs, people who update from previous versions don't get the partition until they clean install next time. The space makes sense as many times people couldn't get updates in the past as they didn't have space to download them, this reserves the space for windows updates of the future,
 
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Endre

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it appears to me that you have no choice.

As brittechguy pointed out, the 3 extra partitions are not very big, the most you will lose is 600mb (maybe - see last sentence) which on a 2tb drive, is nothing at all.

Recovery partition is used for when/if you need to boot PC into advanced startup, which is useful for all sorts of things. Also used for resets. (499mb)
EFI partition is necessary as its the boot partition (100mb)
C: - obvious what this is.

OEM partition -this is created after a windows version update and contains the files currently in the windows.old folder (windows.old is the contents of the previous version of win 10 in case you need to roll back to it). This may not be created during install process **

Even if you could only have C & D on the drive, the next version update (due in 6 months) will create the OEM partition.

I would just let windows create the partitions it needs, and then after that stage, during installation, you can resize C drive and create D.

**There might be another partition created as starting from Version 1903, Windows now saves 16gb of space for future updates. I don't know if this is included in the OEM partition, as it only applies to clean installs, people who update from previous versions don't get the partition until they clean install next time. The space makes sense as many times people couldn't get updates in the past as they didn't have space to download them, this reserves the space for windows updates of the future,

I did find a solution after all!
I deleted all the partitions, recreated them with AOMEI Partition Assistant, formated the partition as MBR (instead of GPT).
Loaded the “legacy” boot settings.
Installed Windows 10.

But I did observe an interesting fact: if I partition my SSD into 2 different GPT partitions, Windows will no longer make those extra partitions! It only does them if you have a single partition on an entire drive.
 
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britechguy

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Serious question with no snark intended: Why would one want to use legacy setup and MBR on newer hardware?

There are very distinct advantages to the newer UEFI and GPT conventions, many of which have been touched upon here.

The amount of space saved hardly seems worth the proverbial "bucket of warm spit" if the occasion arises (and, believe me, it eventually will on some machine one does the legacy tricks on where those are not needed) where you need, or at least really want, some of the recovery options that are only provided by using current conventions.
 

britechguy

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Well, I'm not questioning anyone's right to do exactly as they see fit.

I do, sometimes, want to know the reasoning behind it. Most of the time I find said reasoning lacking, but there are times where I learn something entirely new and unexpected, which is why I ask. I've sometimes learned that what seemed ridiculous to me at first sight was not actually so.

Each of us certainly has the right to assist (or not assist) as our own judgment guides us.
 

Endre

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First of all guys: thank you for the patience and advises.

The truth is that after installing Windows as legacy on the MBR partition; Learning how to do certain things differently (I’ve spent some hours feeding my curiousity), I finally reverted everything to normal: GPT (UEFI), mostly because if I loaded the “BIOS defaults”, my PC wouldn’t boot because it didn’t find the OS (different Boot order), so I realized that this cannot be the right way.
It was a good experience though...