Windows 11 For HP Z840?

[Elbonian]

I long ago resolved the TPM incompatibility for the Windows 11 hardware checker. But it seems that there is no CPU support for any Xeon E5-26xx processors for Windows 11, and the Z840 doesn't seem to accept any CPU chip other than the Xeon E5-26xx CPUs. Does this mean that the Z840 can never use Windows 11? This is very confusing to me. I am very happy with my Z840 (with two  E5-2690 v4 CPUs and 128 GB of RAM). End-of-Support is scheduled for October, 2025. Why is Microsoft refusing to support perfectly good Xeon processors while it continues to support ancient Pentium processors? Is there any solution anywhere on the horizon? Or, must I junk this perfectly good computer when there is no longer any security support from Microsoft?

[patrick521]

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@Elbonianaarpmahjongg wrote:

I long ago resolved the TPM incompatibility for the Windows 11 hardware checker. But it seems that there is no CPU support for any Xeon E5-26xx processors for Windows 11, and the Z840 doesn't seem to accept any CPU chip other than the Xeon E5-26xx CPUs. Does this mean that the Z840 can never use Windows 11? This is very confusing to me. I am very happy with my Z840 (with two  E5-2690 v4 CPUs and 128 GB of RAM). End-of-Support is scheduled for October, 2025. Why is Microsoft refusing to support perfectly good Xeon processors while it continues to support ancient Pentium processors? Is there any solution anywhere on the horizon? Or, must I junk this perfectly good computer when there is no longer any security support from Microsoft?

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Hello, @Elbonianaarpmahjongg

I understand your concern regarding the compatibility of the Xeon E5-26xx series processors with Windows 11. As per the information available, Windows 11 has specific hardware requirements that include a list of supported processors. Unfortunately, the Xeon E5-26xx series processors are not currently on the list of supported CPUs for Windows 11.

The decision to support certain processors is based on factors such as security, reliability, and compatibility with Windows 11’s design principles. Microsoft has stated that they are committed to supporting Windows 10 through October 14, 2025, which means your HP Z840 workstation can continue to receive security updates and function effectively with Windows 10 until then.

Regarding the future, there has been no official announcement from Microsoft about adding support for additional processors to the Windows 11 compatibility list. However, there have been discussions in various communities about workarounds that involve modifying the Windows 11 installer to bypass CPU checks.

I hope this info is helpful to you.

Best Regard,
PATRICK

[NonSequitur777]

@Elbonian,

Welcome to our HP community forum!

You raised some very good questions indeed, and I would like to give you my perspective/recommendations.

You are very correct: your HP Z840 Workstation platform -especially when you upgrade it like you did with one of the best compatible Xeon E5-269x v4 processors money can buy, is far from being obsolete.  One of my recent upgrade projects has been an HP Z440 Workstation, (see link), which happens to be compatible with the same processors as your HP Z840 Workstation.

Just as an FYI: there are a select number of Intel Core processors which are also compatible with your PC:

Link: CPU-Upgrade: Intel Core i7-6800K CPU.

I should know, because I selected an i7-6900K via an eBay Seller and its performance has been most gratifying -but I digress.

Anyway, I would continue to go with Windows 11.  There are a number of ways how to do that, and also to bypass various roadblocks.  Looking past October 2025 though (or actually even right now), what I would do is getting a lean-mean anti-virus program, such as Webroot -which, incidentally, I just renewed with this $30 Amazon killer deal ("1 Year 10 Devices Complete") : Amazon.com: Webroot Internet Security Complete | Antivirus Software 2024 | 10 Device | 1 Year Downlo....

One of my "devices" is an HP ProBook 6560b laptop still running on Windows 7.  I have no worries whatsoever about that, knowing the certainty of a modern and time-tested anti-virus program running in the background.  Besides, come to think of it, even my laptop is still getting the occasional W7 "Security Intelligence" and "Windows Malicious Software" updates.

Hope this was helpful.

Kind Regards,

NonSequitur777

[Elbonian]

You may well have been able to use a Core i7 CPU to upgrade a Z440, which uses a single-socket chipset. However, my Z840 uses a 2-socket chipset and that is not compatible with the Core i7 CPU. Also, half of my 128 GB of ram is attached to each socket, so if I cut it down to one socket, I lose half my RAM. I'm not sure I could get it back by plugging the RAM from the second CPU into the second memory slot of the first CPU (I don't know if this actually works; the Core i7 is supposed to accept 128 GB but I'm not sure which memory slots it would use on the Z840 motherboard). And, in any case, my ECC ram is incompatible with the Core i7 CPU. I'm glad you got it to work on the Z440. But I don't feel good about the Core i7 working on my Z840.

But perhaps what I should do is install a professional firewall behind my AT&T Fiber modem. I've never been a fan of depending upon antivirus to clean up after an infection. I would rather prevent the infection in the first place. I have 16 months to figure out a good solution....

[NonSequitur777]

@Elbonian,

Actually, EEC (RDIMM) RAM is compatible with the Intel Core i7 processors on HP Z440/840 platforms, as I am running 4 x 16GB of Samsung M393A2K43BB1-CTD6Q (DDR4 PC4-21300, 2666 MHz, ECC, Registered DIMM (RDIMM), dual-rank (2Rx8), 288-pin RAM sticks with my i7-6900K.  I was initially surprised, as Intel's specs claim that these processors are not compatible with ECC RAM:

But that is incorrect as I have shown with my system, and, for example, this HP Z840 Workstation User showed that too whilst fitted their rig with dual i7-6850K processors:

With 8 x 4GB of ECC (RDIMM) RAM:

Kind Regards,

NonSequitur777

[NonSequitur777]

@Elbonian,

And yes, installing a professional firewall would provide peace of mind regardless of what OS you use.

Kind Regards,

NonSequitur777

[DGroves · Accepted solution]

on the z820/840 systems each cpu has 8 dimm slots and unless the second cpu is installed it's dimm sockets are not useable by the first cpu for best performance each cpu should have the same number/capacity dimms installed

to install win 11 on these workstations download the official MS windows installer in "ISO" format (not the usb one)

then download "Rufus" this app will read the ISO image and create a patched usb key installer

that bypasses the TPM/CPU checks allowing win 11 installs on unsupported hardware