Any progress please ? We have more than 30 pcs of Dell 5820 Workstations and we need "Resizable BAR Support" for main application. Without Resizable BAR Support is application very limited.

Dell every time redirects this communication to private messages. And in private message "recommends to enable Resizable BAR in BIOS". Regardless of the fact that in the very first message you write to them that this function is not found in the bios.

I dumped my perfectly servicable 5820s because of this issue. If Dell won't maintain their products then I'll find a company that will.

This is not a consumer grade piece of hardware, @DELL-Cares It's a Commercial/Industrial Workstation that has to meet the demands of Data Scientists and Engineers. If you're not going to let us use modern GPUs to their full capacity in them, then come out and say it.

I installed the latest BIOS, Precision_5820_2.39.0.exe, dated Dec 17, 2024.

Still there is no REBAR support in the options.

Give us the actual BIOS files, not the exe, so we can patch it ourselves!

GitHub - xCuri0/ReBarUEFI: Resizable BAR for (almost) any UEFI system

The only missing piece to the puzzle is "Resizable BAR enabled in BIOS".

That's sad.

I just installed BIOS 2.43.0 released Jun 15 2025. Still no rebar. I have the xeon model.
I am having a hard time understanding why not. xCuri0 in his spare time has created a means of patching BIOS files with rebar support. ReBarUEFI on GitHub.
If it is a feature than can be added to the BIOS, why hasn't it been added. It seems it is only on low level motherboards that this feature is not included. The manufacture date on my T5280 is 07-06-2023. About 2 years old. When I purchased it, I did not consider it a low level computer and the price was definitely not low level.
I ordered an intel arc a770 on ebay with a no return policy, so am forced to make it work somehow. I am retired and living on a fix income, so this was a big ticket purchase for me. I can't afford purchasing another video card that doesn't require rebar.  I did not even know rebar was a thing, until I started researching Linux drivers while waiting for delivery. Intel arc requires rebar on Windows too, so please don't side step with we don't support Linux.
On GitHub 2 people have claimed to get the rebar patch to work on T5810 and tekbred on this thread has claimed to get rebar working.
I really don't like the idea of a patched BIOS, that could possibly brick my computer. These low end motherboards don't have dual BIOS.
Has anyone made rebar work and want to share their method?

Hi Dell Support, it is now the middle of May 2026 and we still don't have a Resizable BAR option in our T5820 BIOS menu.

Please can you work on adding this feature in the next release?

The equivalent HP Z4 G4 workstation had its Resizable BAR (Base Address Registers) feature enabled in a BIOS update 2.71 which was released in July 2021!

Please restore our faith in Dell's support updates.  Your hardware itself is usually rock-solid but good hardware is useless without accompanying, up-to-date firmware.

Many thanks.

Hi @DELL-Nat M   I think this thread is worth checking out.

It took 3-4 tries to post this in Android 16 Edge.

With the help of a brilliant gent I met on github, I was able to completely resolve this issue on our T7920s. I believe the same solution will work on our 5820s. I intend to find out this weekend. Check out my posts relating to the same issue with the 7920s here on the forum. If there's enough interest, I'll post the process I follow. I have every reason to believe it will work just as well there. I'm running 2 intel arc pro b70s on the 7920 and I intend to add a third this weekend. I also plan to run 2 of the same GPUs in the first 5820. BTW - for those of you expressing frustration with Dell over this - I'm right there with you. Dell could have resolved this issue 100% on the 7920 by simply exposing an existing setting in the BIOS config screen. I mean... seriously? The setting exists in NVRAM. Dell could expose it so we could set it in BIOS. For some reason they refuse. Makes no sense. I suspect this is exactly what's going on with the 5820. More to come...

@robarola Please post the full instructions. I also have Arc cards "working" in a 5820, but Resizable BAR is not active.