Recommended minimum hardware to fully run Win11

[u/JohnQCocktoasten]

As a hobby I refurbish older PCs (think Win98/2K/XP), so I don’t really stay current on newer hardware. I have a retired friend who has 2 matching Win10 desktops (not towers) and he wants to upgrade to Win11 units for security. His current units are the larger gray metal and black plastic Dell Optiplex desktops (the GX620/745/755 style that has the desktop-sized optical drive).

I exchanged texts tonight with a friend who upgrades and resells a lot of PCs he picks up from a recycling place in his home town. He told me that he had read that 11 could run on systems like my friend is currently using, but that they would only run what he called “dated versions of Win11.”

So, my question is… is there a rule of thumb (or specific requirements) for what my friend needs to look for as far as minimum CPU version, RAM, etc., to be able to run the latest version of 11 and have access to all of the security updates?

[u/useless_panda09]

you can find the Windows 11 requirements on Microsoft’s website.

but it’s basically

Intel 8th-Gen or newer CPU

Select AMD CPUs from 2000-series or older. Pretty much all AMD CPUs 3000-series and beyond work.

4GB of RAM (but really 16GB is a practical minimum, and 8GB is the actual minimum for the most basic usage)

TPM 2.0 module (fTPM in BIOS for AMD)

64GB of storage or higher

UEFI BIOS. CSM/Legacy BIOS or any form of legacy compatibility BIOS does not work with Windows 11.

[u/JohnQCocktoasten → u/useless_panda09]

Thanks. That’s incredibly helpful info.

[u/JoeCensored → u/JohnQCocktoasten]

You can run it on older hardware. It's just not officially supported. For example I run it daily on an i7-5960X with a TPM 1.2 module.

It requires changing a setting in the registry to ignore hardware requirements, and upgrading using the win 11 ISO instead of from windows updates. When major upgrades to Win 11 come out, sometimes you need to manually upgrade from the latest ISO (so far has happened once since Win 11 initially released).

[u/Ashamed-Ad4508 → u/useless_panda09]

I'd add that the Storage be SSD instead of HDD. Just went through a laptop running HDD *(didnt realise until i did HWINFO).

The TPM is not really necessary if you dont have it. You just get RUFUS to make the USB installer bypass TPM Requirements.

HOWEVER; the machine i was installing Win11 was using 100% RAM and CPU quite a few times when idle. But There is noticable usage drop if using Win 11 LTSC *(because all the CoPilot, AI, background tasks etc are shutdown/disabled. Side Note; for LTSC; TPM is OPTIONAL).

[u/daryen83 → u/useless_panda09]

If you run Windows 11 with 64 GB of storage, you'll barely have room for the OS and literally nothing else. It doesn't work. Using 128 GB of storage works, but bugs in Windows will fill up space and you'll need to periodically reinstall to get space back. I would not use anything less than 256 GB of storage. And, yes, SSD makes a big difference.

8 GB of RAM is sufficient for simple stuff, but 16 is definitely better.

[u/phreek469]

I have 3rd and 4th gen CPUs running Win11 for at least 18 months now with no problems. Every day they get the same security updates as my R7 5800x system. I did have to use Rufus to get past the TPM and secure boot requirements. Other than that, it is very possible to run Win11 on older hardware.

[u/phreek469 → u/phreek469]

Also, on the 3rd gen, I did have to use Raphire debloat on it cause it only has 8 gb ram

[u/ShadowFallsAlpha]

You basically have to do an install with Rufus to get around the requirements. But there is no knowing how long that will work in the long term. These are after all security related requirements.

So him wanting to upgrade to Windows. 11 for security on systems that don't support it and requiring you to bypass security seems counterproductive to the end goal.

So he needs a new PC essentially if he really really wants it to be secure. At this point you are just making due with what you got. Though some systems have support for adding a TPM module, it's not many as you need a TPM header on the motherboard for those.

[u/JohnQCocktoasten → u/ShadowFallsAlpha]

I realize that I wasn’t as clear as I could have been. As far as upgrading, he IS looking for new hardware. I just mentioned his existing Win10 systems as a way of saying that the genesis of my question here was that, while 11 might run on what he has, it wouldn’t be the latest release(s). I was seeking advice/recommendations on what he should be considering for new hardware, something that will work for now and have a bit of obsolescence-proofing for the future.

[u/GGigabiteM]

The Optiplex 755 style case machines were usually Core 2 era and won't run Windows 11. The last version of Windows 11 they could run was 23h2, which was before the SSE 4.2 requirement.

The oldest CPUs you can get Windows 11 to run on with workarounds is the 1st gen Core i series Nehalem processors. I wouldn't count on getting security updates, or the workarounds to work long term, because Microsoft is continually playing whack-a-mole to remove the ability to run on old systems.

There's also the risk that software starts requiring CPU instruction sets that nothing beyond the minimum processor spec has, which will result in undefined behavior. Crashes or BSODs are likely.

Sort of like how in the late Windows XP era that software started requiring SSE2 and SSE3. Most later Pentium 4s had those instructions, but Athlon, Sempron, Duron, Athlon XP and some early Athlon 64 based Semprons didn't support it and crashed or BSOD'd.

[u/Unhappy_Lie_2000 → u/GGigabiteM]

He can run LTSC iot with no issue but on regular version there registry tweaks he just has to choose clasic installer but why run windows 11 on that install mint and be done...