We could merge with this one or a similar thread from a more recent time.
Started in 2021 the most recent post is from 2023 so it has a good shelf life already.
Or perhaps a new dedicated Pc Building off topic to match our Base Building on topic thread.
A question for the community:
I have an old computer, an original i7 dating back to 2009, with graphics upgraded to GTX 1080 in 2016. The O/S has been upgraded from Win 7 Pro to Win 10 Pro. It still works, mostly, but itâs tired and slow and it wonât run Windows 11.
The original Win 7 Pro operating system was legitimately purchased and registered.
If I were to change out the motherboard and processor for something more modern and Windows 11 compatible, would I be able to keep my current operating system?
I canât find any sensible information from Microsoft. They seem to assume I will buy a new computer, with Win 11 pre-installed.
Asking my tech pro 
my son. He has built a number of PCs for people, some of whom have requested similar things. I believe the key lay in not taking it online and having a physical copy of Win10. And what is on the tiny USB that comes with some Win10 packages is not a full copy. Microsoft is choking Win10 to death. I am not sure you can download it any moreâŚhopefully he will respond soon.
My understanding is the copy of windows is registered to a serial in yr mobo or bios so a new mobo essentially means a new computer to windows licensing.
You might be able to contact an actual human technician on their end who might wave a magic wand and re-register to new mobo serial, but it feels like theyâre doing that with less frequency these days, if even at all.
I was hoping not to install Win 10. The idea ATM is to pull the existing motherboard and processor, replace them with more modern equivalents, then power the system back up again, keeping the existing HDDs and operating system.
In the past, Microsoft wouldnât let you do this - the validation of your operating system was digitally locked to your hardware. If you changed too much of the hardware, you ended up with an unregistered and unsupported operating system. The only solution was to buy a new O/S - and retail copies of Win 11 Pro are expensive.
The Win 10 Pro the computer is running didnât come from a disk. It was upgraded online from Win 7 Pro. So I donât have a Win 10 Pro disk.
In any case, the whole object of the exercise is to make the computer capable of upgrading to Win 11 Pro - which, at the moment, the hardware wonât allow.
(edit) Sorry, @toddumptious - my reply crossed over yours in typing, The thing with the mobo being registered to the O/S is exactly the problem Iâm investigating.
Thanks @toddumptious . I do remember now my son was talking about reusing a motherboard. Windows is written on in such a way as to render reusing it with another OS like Linux impossible. But I donât know how it affects another version of Windows. I will reask the question to see if he has encountered this.
@Polyphemus here is his reply
Product keys are tied to motherboards. If you swap motherboards, you will have your OS de-registered upon startup. MS considers a new motherboard a new computer.
Win7 keys could be used on up to 3 motherboards.
It is possible that, since the Win7 product key has been used for a Win10 upgrade, that one could use it to install Win10, then upgrade to Win11, but take note: I donât know if the newest CPUâs have support for Win10 (Win7 only had support up to AMDâs FX CPUâs officially. AM5 socket CPUâs released after Win10 went into extended support, so Iâm not sure. AM4 I know is just fine.)
I say, swap to a new board, and if the key doesnât work, well, youâll just have to buy direct from MS and put it in. A Win10 key will upgrade to Win11, so itâs no harm done there.
Or, install EndeavourOS and pay nothing. 
I sent him your reply above about your intent
Thanks for your efforts, and please thank your son for his. The situation seems to be pretty much as I feared.
I donât want to scrap the old computer if it can be saved - it served me well in the past, thereâs a lot of software on there thatâs no longer available, and some of the parts are still very desirable (for instance, it has a 1,000 watt PSU - I didnât mess about in those days). So if I can drag it into the current era, I would like to.
At the moment, though, this is just a feasibility study. Once I know if it can be done, then Iâll decide whether I will.
Another reply;
cpu, motherboard, and ram are the only 3 things thatâll have to be replaced. And the heatsink if you donât want stock (AMDâs stock heatsinks ainât half bad tbh). The rest will carry over just fine, no doubt in my mind. Connections have remained pretty much the same since that gen 1 i7; That 1k Watt PSU will carry over. GPU, case, and any drives will physically connect as well. Sure, thereâs 12-16 pins for CPUâs now, but if you have a 65w tdp on your CPU⌠The 8-pin on the PSU is just fine.
Itâs a 1,000 watt PSU. If you know the pinout voltages, there are adaptors available. There shouldnât be any problem with the PSU supplying the necessary current.
Wait, you get an OM license with a motherboard these days? WTF?
No, when you install Windows on a new motherboard, it creates a hash based on certain hardware items - and that hash forms part of your product key.
If you change the hardware, your operating system wonât work any more.
Correct. That is what he meant.
I wanted to reuse my last motherboard with Linux but that is a no-go. So I bought all new stuff except for a few components. Kept my hard drive because it has a disc burner
I think thatâs a dfferent problem. If you allow it (or if the computer manufacturer allows it) Windows can encrypt and lock the UEFI bios. Once thatâs been done, you canât install another operating system. If you did it yourself, you should have a password to unlock it again. If it was done by a previous owner, or by the manufacturer, then youâre stuck.
I was supposed to be dual booting with Win 10 and Linux but it kept going back to Win 10 and would not even give me the dual boot screen. Never did figure out what the issue was.
I needed new hardware anyway so built a new PC, went Linux and grabbed a cheap laptop with Win 11 pre installed in case I needed it.
Never haveâŚ
In 2022 I assembled a new PC and installed the current Win 11 Pro OS. Tried and failed to get it to accept my upgraded Win 10 Pro key. Contacted MS Support. I still had my purchased Win XP Pro key (and disks) but that didnât work either. MS Support kept asking if I had a more recent key. Took until the next day to remember that I did have a Win 8 Pro key (and disks) which worked. That key activated my Win 11 Pro OS.
The problem seems to be that the thin copper tracks on motherboard and graphics card printed circuits canât cope with the current required by modern CPUs and graphics processors.
In the bad old lo-tech days, we would have solved that by soldering a couple of honking big wires onto the back of the PCB - and the problem would go away.
It seems that nowadays thatâs too simple. The answer now is whole new sets of power connectors, and the wiring to serve them, all over the place, cluttering up the case, and increasing the chance of accidentally making a wrong connection.
Progress.
Wires and copper were too simple in the past,these days they wonât work without a colony of activated nano bot bacteria that allows for maximum current flow with minimal bleed. To the human eye it just looks like basic wire covering but itâs very much alive and it knows your search history.
Surprising, I remembered the password for this accountâŚ
The main issue with her board was it being AM3+, the FX-8350 just wasnât going to cut it for down the road for her use-case. I threw that board in a case that housed a broken Pentium III board in it because itâs still wholly usable in its own right. The UEFI business, I, donât like either. The computers at work are all UEFI locked machines, it takes me a moment to get ArchLinux booting off a flashdrive for hardware work on them (Imagine cloning from HDD to M.2 drives, Windows donât like that at all, ha!)
The dual-booting issue mentioned was weird. I had it booting up to GRUB first, but if you booted Windows more times than you booted the Linux install, it would default the UEFI to booting Windows instead and bypass GRUB alltogether. One of the reasons I came to dislike UEFI. For single-OS rigs, itâs fine, but multi-OS? Headache, to me at least.
It is possible to at least remove the UEFI listing for Windows off of a board; Iâve done that here myself once. Makes it clean enough. Iâm the odd one out, I still run an MBR installation to this day in Arch; I like knowing I can take it out, drop it to a new build, and it just works. Peace of mind that UEFI doesnât give. Itâs not really MBR; Itâs a GPT, just use that in place of MBR. So, bigger drives, no MBR quirks, but a simple setup. One big olâ partition to make the platters go 'round.
Huh⌠what a dick move!