News Existing workarounds fail with new Windows 11 requirement that invalidates older CPUs — Microsoft's PopCnt restriction appears to be unbreakable

[Admin]

PopCnt is a CPU instruction that will be required to run Windows 11 starting with 24H2. But unlike TPM or Secure Boot, enthusiasts have found that the PopCnt requirement cannot be bypassed. Any attempts to bypass it lead to boot failure.

Existing workarounds fail with new Windows 11 requirement that invalidates older CPUs — Microsoft's PopCnt restriction appears to be unbreakable : Read more

 

[Zaranthos]

Until someone does something clever like make a memory resident CPU instruction emulator or something maybe. Unbreakable will just be a challenge to some bored developer who says "hold my beer". Haha.

 

[USAFRet]

And when the workarounds first came out, a couple of people around here laughed at me for not immediately updating my non-compatible hardware to Win 11.

"Why wouldn't you do this?"
'well, there's no hurry....let's see what the future holds'

 

[Alvar "Miles" Udell]

Windows 11 runs like mud on my Surface Pro 3 i7 from 2014, I don't want to know how slow it runs on something from 2008 or 2004.

 

[yeyibi]

popcount can be emulated, but that would require patching any program that uses it, and it would be slow.

 

[voyteck]

Again, this issue will only affect the extremely few enthusiasts committed to running Windows 11 on ancient computer hardware.

I'm quite the opposite of enthusiast but I run my Windows (still 10) on a Q9550 system. It's my secondary PC, which I use for work (copy editing, which in my country is paid abysmally bad so this qualifies as a problem). Unfortunately, my primary PC, which is located in my living room and which I use at night and/or for gaming, belongs to my girlfriend. Anyway, I need two.

 

[USAFRet]

I'm quite the opposite of enthusiast but I run my Windows (still 10) on a Q9550 system. It's my secondary PC, which I use for work (copy editing, which in my country is paid abysmally bad so this qualifies as a problem). Unfortunately, my primary PC, which is located in my living room and which I use at night and/or for gaming, belongs to my girlfriend. Anyway, I need two.

Win 10 is fine.
It is 11 that is the issue with older hardware.

 

[voyteck]

Win 10 is fine.
It is 11 that is the issue with older hardware.

It's fine for now. Until October 2025, when the extended support ends. And I have to use Windows/Word even for work.

 

[baboma]

>If a system fails to meet Windows 11's minimum requirements, the upgrade wizard (for this particular build) will tell users that PopCnt isn't supported on the chip. Microsoft puts this requirement at the top of its requirements list, saying, "This PC's processor doesn't support a critical feature (PopCnt)."

I have a variety of old laptops running on Win11, some of which probably won't pass this. The above is good enough for me. I don't need to have the latest/greatest rev on the older PCs; I just need a fail-aware install that won't brick my existing Win11 boxes, and the above is fine. I don't need any more workaround.

Why do I want Win11 on older boxes? I want to standardize on a single Win version as much as possible, just for the consistency of having the same interface/tools.

 

[USAFRet]

It's fine for now. Until October 2025, when the extended support ends. And I have to use Windows/Word even for work.

This is true.

But just about any system built in the last 6 years (2018ish) is Win 11 capable. All the way back to an i3-8100, in Q4 2017.

This issue is for systems much older than that.

 

[TerryLaze]

And when the workarounds first came out, a couple of people around here laughed at me for not immediately updating my non-compatible hardware to Win 11.

"Why wouldn't you do this?"
'well, there's no hurry....let's see what the future holds'

It's not like any of these people suggested using a pre 2005 PC for windows 11....
Anybody that installed win 11 with the bypass on a semi-recent system is not affected by this.

 

[RussG]

I wonder what other CPU instructions Windows could be taking advantage of that it isn't. I'd prefer they use everything they can for speed reasons.

 

[TerryLaze]

I'd prefer they use everything they can for speed reasons.

Yeah but they should also maintain at least one version of windows that can run on old crap. Call it porthole or something so that people that want windows don't get confused.

 

[BillyBuerger]

This is true.

But just about any system built in the last 6 years (2018ish) is Win 11 capable. All the way back to an i3-8100, in Q4 2017.

This issue is for systems much older than that.

Or a system that is only 1 year older. I picked up a PC in 2018 for my in-laws that has an i5-7500 CPU. Perfectly usable from a performance standpoint. But since I bought it 1 year too late, it's now trash and we'll have to replace it for them.

 

[USAFRet]

Or a system that is only 1 year older. I picked up a PC in 2018 for my in-laws that has an i5-7500 CPU. Perfectly usable from a performance standpoint. But since I bought it 1 year too late, it's now trash and we'll have to replace it for them.

Well, yes.
There was a cutoff. Unfortunately, your system is on the wrong side.

But again, that system will be 7 years old when Win 10 falls off mainstream support.

 

[stonecarver]

From the story

Thankfully, PopCnt has been supported since the Intel Nehalem and AMD Phenom II era — 14 years ago -- so compatibility won't be an issue for any modern systems. The only users that will be affected are enthusiasts running modified versions of Windows 11 on 15+ year-old chips like Core 2 Duos or Athlon 64's.

So if I understand correctly Core 2 Duos along with the Athlons are the end of the line.

Anything newer is okie dokie nothing to stress over or am I missing something.

 

[thestryker]

The arbitrary way MS has approached Win11 requirements has been disappointing from the start. The spare box my dad used is a C2D which runs Win10 just fine and if not for arbitrary reasons would be able to run Win11 too. If he still used it I would probably have to pickup something new for him since none of my spare hardware natively supports Win11.

I get that time moves on and whatnot, but there really hasn't been a good reason for the prevention of hardware running. I'm not saying they need to support literally everything, but there have been workarounds for everything until this which is what makes their limits arbitrary.

 

[ezst036]

It's fine for now. Until October 2025, when the extended support ends. And I have to use Windows/Word even for work.

I wonder how well Windows 11 would work on a Core 2 Duo that has Linux installed and W11 in Virtualbox or another VM.

I suspect Microsoft has "accounted" for this scenario but I'd like to see someone who has the hardware give it a try and tell the results.

Windows 10 would obviously continue to provide value, even after 2025, being sandboxed in a VM.

 

[stonecarver]

Something I have been running through my head is ok the core 2 Duo and the Athlon are moving forward kicked out. But still does not mean Windows 11 PRE this latest Windows 11 with 24H2 update.

I know you can prevent some updates from installing not sure if and what voodoo would need to take place.

Not cheerleading the old system still use Windows 11 just thinking out loud.

 

[TerryLaze]

I wonder how well Windows 11 would work on a Core 2 Duo that has Linux installed and W11 in Virtualbox or another VM.

I suspect Microsoft has "accounted" for this scenario but I'd like to see someone who has the hardware give it a try and tell the results.

Windows 10 would obviously continue to provide value, even after 2025, being sandboxed in a VM.

It would run horribly since core 2 doesn't have any virtualization.

 

[ezst036]

It would run horribly since core 2 doesn't have any virtualization.

Yikes. I didn't think about that.

 

[beingDino]

Or a system that is only 1 year older. I picked up a PC in 2018 for my in-laws that has an i5-7500 CPU. Perfectly usable from a performance standpoint. But since I bought it 1 year too late, it's now trash and we'll have to replace it for them.

With very little effort, you can upgrade that machine to Win11. Since its much newer that the Core2 Duo machines, you should be fine

 

[jbo5112]

popcount can be emulated, but that would require patching any program that uses it, and it would be slow.

I had an AMD FX-6300 system that had the popcount hardware intruction, but gcc/g++ wouldn't use it (yes, I tried the optimizer flags). I finally forced the instruction through assembly coding, and found that the hardware instruction was considerably slower.