That system does not meet the requirements for Windows 11 -- the CPU is 7th generation.  Supported CPUs start with the next (8th).

Windows 11 may run (at least for now) but will never be officially supported -- Dell did not make that decision;  Microsoft did.

Dell precision 5520 and Surface Studio 2 both of them have the same processor.

This is not fair from Dell as well as Microsoft. In future i am not going to buy anything from Dell #IndiaboycottDell #IndiaboycottMicrosoft.

#Intel step forward for your chip.

• Yes please share the details how you did it. I still haven't resolved it.

Hi. Have you been able to resolve this? Succeeded with my 5480. I may be able to help you.

Sorry but this position is incorrect. I own an inpsiron 13 6th generation running windows 11

Actually Microsoft has published a list of processors supported by Windows 11 and that list is here. And though you may have the same CPU as the Surface 2 make note of the caveat that MS put on the i7-7820HQ.

And this from their notes on that page:

Windows 11 Intel® Core™ i7-7820HQ Supported Systems

Dell Precision 5520
Surface Studio 2

10/4/2021: Page updated to remove Lenovo device from list

Now can you install Windows 11, absolutely. By going to this page and downloading the media creation tool, you can install Windows 11 from the install flash drive that is created and it will bypass the CPU check on your system. And as mentioned by @ejn63 , this is an MS decision and all manufacturers, not just Dell, are having the same restrictions. That media creation tool is the 2nd choice on the page. And yes I am running Windows 11 on an old Dell Latitude E5430.

Keep in mind that should you need service in the future, Dell tech support will insist that you install Windows 10 before they offer any assistance.

First. Follow this link to enable secure boot from your bios. Back up every important file.

https://www.dell.com/support/kbdoc/en-us/000190116/How-to-Enable-Secure-Boot-on-Your-Dell-Device

Second. Follow this to change from mbr to gpt.

https://www.diskgenius.com/how-to/the-selected-disk-has-an-mbr-partition-table.php

Best regards

It may be running Windows 11, but that's because you bypassed the installation requirements for it.  The system you have does not and never will  have official Windows 11 support.

Yes, it runs -- for now.  An update is coming that will push a desktop wallpaper with "running on an unsupported system", and Microsoft has publicly stated that it reserves the right to release future updates that enforce the CPU requirement.  Be prepared for that day - in other words, if this is a work system, make sure you can go back to Windows 10 when needed.

The Dell 5480 has the same 7820hq processor as the MS Surface 2 which is being updated to windows 11.  I find this distressing and don't know why no one at Dell has not objected to MS. They should be in our corner on this and support their loyal Dell users. I have had over 6 Dell computers and tablets and have touted and recommended Dell for the last 30 years! As an aside, I have a friend who has a Surface 2 that just had the battery die. The case is glued and can not be customer replaced. Over $400 to install a new one.

Today I booted into windows 10 and it offered to upgrade my computer to windows 11.  I had just updated my intel graphics 630 driver to  31.0.101.2115. I declined and went back to PCHealth Check and it said it wasn't eligible for windows 11 upgrade due to processor. I'm confused.