As Microsoft continues to develop Windows 11 25H2 (Beta), many users are wondering whether this new version can still be installed on older, unsupported computers. In this article, we provide a full hands-on test using two machines: one with an aging Intel Core 2 Duo processor and another with a 7th-generation Intel i7 CPU. The results reveal both the limitations and possibilities with 25H2.
This is not speculation — this is a real-world test with clear steps and honest outcomes. Here’s what happened.
Testing on the Core 2 Duo – A 15-Year-Old PC
The first machine we tested was equipped with a Core 2 Duo processor, which is more than a decade old. These CPUs lack two critical features now required by Windows 11: SSE4.2 and POPCNT.
We started by attempting installation using the familiar setup /product server method, which previously helped bypass TPM and Secure Boot. However, this time, the installer presented a new and unexpected error:
“This PC’s processor does not support critical feature: POPCNT”
“SSE4.2 is not supported”
Despite using known bypass tools, registry tweaks, and even clean install attempts with Rufus and modified ISOs, we hit a hard stop. Microsoft has now embedded these requirements directly into the kernel, making it impossible to proceed on CPUs without these instructions.
Result: Installation failed on the Core 2 Duo, and no bypass method worked.
Testing on the 7th Gen Intel i7 – Still Unsupported, But Works
The second test system was a 7th Gen Intel i7-7700K, which is technically unsupported by Windows 11, but does include both SSE4.2 and POPCNT. After running a quick check with tools like CPU-Z and Microsoft’s PC Health Check, we confirmed those features were present.
We then converted the system drive from MBR to GPT, used an updated bypass script from GitHub (called BW11), and attempted the upgrade.
The result? Success. The system installed Windows 11 25H2 Developer Preview without issue. All files, apps, and settings were preserved.
We verified the version by checking the system folders and confirmed the presence of build GE 25H2.
Result: Installation successful on 7th Gen Intel using updated methods.
Why SSE4.2 and POPCNT Now Matter More Than Ever
Unlike past versions of Windows 11, the 25H2 release enforces SSE4.2 and POPCNT support at the kernel level. This means bypassing the requirement is no longer as simple as editing a registry key or disabling a feature during setup. The lack of these CPU instructions will immediately halt the installation process.
Older processors like Core 2 Duo, Core 2 Quad, and many older AMD chips are now excluded from the possibility of running 25H2.
What You Can Do If You Have an Old PC
If you’re using an older PC that lacks SSE4.2 or POPCNT, here are your best options:
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Continue using Windows 11 23H2, which still works well on many unsupported systems.
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Consider switching to Tiny11 or similar lightweight builds based on older versions.
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Wait for our upcoming recommendations on the best post-Windows 10 upgrade paths after support ends in October 2025.
Feature Core 2 Duo Intel i7 (7th Gen) SSE4.2 Support No Yes POPCNT Support No Yes TPM 2.0 Required No (Bypassed) No (Bypassed) Secure Boot Required No (Bypassed) No (Bypassed) Final Result Failed Success
Tools and Scripts Used
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Windows 11 25H2 Insider Preview ISO
Windows Insider -
Setup script with
product serverswitch- Open the file and paste the following code:
setup /product server2. Save the file and close it or you can use the file below prepaired.
Download Setup.bat -
BW11 bypass script (GitHub)
Download BW11.bat -
Rufus for bootable USB creation
Rufus Website -
MBR2GPT Script:
Alternatively, you can use the command prompt (CMD) with the following commands to perform the conversion:
mbr2gpt /validate /allowFullOSmbr2gpt /convert /allowFullOS -
CPU-Z for hardware feature detection
CPUZ Website
Check Windows Language version CMD Command:
dism /online /get-intlAll links to the tools and resources mentioned are included at the end of this post.
Final Thoughts
Windows 11 25H2 introduces new hardware restrictions that go beyond TPM and Secure Boot. With SSE4.2 and POPCNT now required at the kernel level, it marks the end of compatibility for many older systems.
However, if your PC has these features — even if it’s still not on Microsoft’s official list — you may still be able to upgrade with the right preparation. The 7th Gen Intel system is a great example of that.
For those stuck on older hardware, 23H2 remains a stable and fast alternative.
