Windows 11 definitely stops working on older processors

The official system requirements for Windows 11 are much higher than the previous Windows 10 version of the operating system, but there are workarounds for installing on computers with older generations of hardware. However, some of those older computers definitely won’t be able to run Windows 11 anymore because of the latest CPU instruction update.

Back in February, Microsoft began testing Windows 11 versions that required POPCNT CPU instructions to execute certain system operations. At that time it was not clear whether the change was intentional or accidental, it is just a fact that the newer Windows 11 Build 26080 will not even start if the processor does not support the POPCNT instruction set. Instead, Windows 11 will get stuck in a reboot loop, over and over again. Microsoft declined to comment on the change when asked by The Register.

The POPCNT CPU instruction set is part of the SSE4.2 instruction set. Intel added it with the first generation of Core i5 and Core i7 processors with Nehalem architecture back in 2008. On the other hand, AMD processors received the same set of instructions with the Bulldozer generation in 2013. POPCNT instructions were also supported on earlier AMD CPU models, but only as an incomplete set of SSE4a instructions, which the new Windows 11 does not seem to support. Unfortunately, there is no workaround for missing CPU instructions.

Definitely goodbye to Windows 11 on old computers

The official system requirements for Microsoft Windows 11 have so far already included eighth-generation Intel Core processors and higher, or second-generation Ryzen processors and higher. There are also other CPU models with support for PC features like TPM 2.0.

The new change only affects users who bypassed the official requirements on computers with older processors. If you have a computer that doesn’t meet the official requirements, such as a first-generation Ryzen laptop or a desktop with a seventh-generation Intel Core processor, you’re still safe for now.

As for older processors, they were never intended or intended to run Windows 11, so this latest change is quite inconvenient for their owners. Making matters worse is Microsoft’s decision to end support for the Windows 10 operating system in October 2025, unless you pay for software support – we still don’t know how much that will cost.

If you have a computer with an older processor, you will need to temporarily revert to Windows 10 or try your luck with another operating system, such as a Linux distribution. However, some apps and games don’t even work without the aforementioned CPU instructions, such as the ultra-popular Apex Legends game.

A new version of the Windows operating system could arrive as early as this year, possibly called Windows 12, and could have even more rigorous system requirements than the Windows 11 version. However, all processors that do not support POPCNT instructions are already officially unsupported and removed from the list, and many computers with such old hardware are probably still running older versions of the Windows operating system anyway, reports howtogeek.