W11 25H2 on unsupported HP hardware...

[SDH]

The official Microsoft release of W11 25H2 is right around the corner. You may have heard that it is activated by an enablement package which turns on code that Microsoft has already pre-installed on your 24H2 install if you've been updating it.

Here's the scoop on how that works on our officially unsupported HP workstations that are successfully running W11 24H2:

Just as well as if they were officially supported HP workstations, and just as quickly. I've done that on both types here now.

We're near Redmond, and I've obtained an official enablement package (167 KB in size, MS digital signature 9/19/25) and it runs and upgrades HP workstations in both situations in seconds. Then, after reboot, Windows Update also detects some W11 25H2 updates and installs them, all without need for an in-place or clean install OS upgrade.

Nice to know now, but I'd recommend waiting a bit for the broad release of that enablement package.

[SDH]

UPDATE:

This W11 25H2 upgrade method is working as fast and as reliably on all the W11 24H2 officially supported and officially unsupported added HP hardware I've tested it on here, to include:

Z420 v2/ Z620 v2 workstations including those I've upgraded here to running off OPROM-enabled Intel P3700 PCIe add-in-cards, and Samsung 950 Pro NVMe boot drives in HP ZTD PCIe cards, and 2.5" SATA boot SSDs. I have no reason to believe the same would not be true with the Z420 and Z620 v1 versions and the Z820 workstations... just don't have those here to test on. The OPROM HowTo is HERE.

Z440/ Z640 workstations with v4 processors. Also don't have the Z840, or older v3 processor ones to test on.

Z4 G4 Xeon workstations which are all W11 officially supported.

HP business laptops (all officially W11 supported) and several older officially W11 unsupported Dell and Lenovo laptops.

Elite 8300 SFF business class computers with Samsung 950 Pro OPROM-enabled M.2 NVMe boot drives mounted in HP ZTD PCIe cards (with the ZTD card having the Q1-out modification). These each have been processor-upgraded to the Core i7-3770 for best speed and to enable PCIe Gen3 bandwidth in the processor-controlled long dark "PCI Express x16" slot, and each has a nVidia K620 video card in the long white "PCI Express x16 downshifted to a x4" slot. That white slot is instead controlled by the soldered-on Q77 Express chipset and thus can only ever function (but very well) at PCIe Gen2 bandwidth. The same success with a little less overall speed can be accomplished at lower recycled-processor-cost via the HP approved Core i5-3570 or i5-3470. Same methods would also work for the CMT tower version.

[SDH]

Couple of Z600's now too...