Testing please: GPU-Z Resizable BAR Support Report

[Mussels]

cant enable SAM in control pannel as i said its says not available for me, i dont meantion but yes i have "a UEFI installed OS with CSM disabled in the BIOS, above 4G decoding and REBAR enabled" all of this on when i meantioned resible bar is on.

So how can i know i cant use the resible bar or not?

You just said you cant, since the AMD driver wont let you enable it

This does contradict what GPU-Z reports, @W1zzard may need you to export a log file or send additional screenshots to find out what's going on here - AMD may have added partial support, or it may be a reporting error

 

[W1zzard]

You just said you cant, since the AMD driver wont let you enable it

This does contradict what GPU-Z reports, @W1zzard may need you to export a log file or send additional screenshots to find out what's going on here - AMD may have added partial support, or it may be a reporting error

Not sure what logs I could ask for. The BAR is sized at 8 GB, there's no doubt about that. and that's the definition of Resizable BAR.

 

[Mussels]

Not sure what logs I could ask for. The BAR is sized at 8 GB, there's no doubt about that. and that's the definition of Resizable BAR.

In the past you wanted to find certain registry settings and similar - he cant enable it, but GPU-Z says it is enabled
Theres a contradiction

 

[W1zzard]

In the past you wanted to find certain registry settings and similar - he cant enable it, but GPU-Z says it is enabled
Theres a contradiction

You mean Resources in Device Manager? That will show a 8 GB BAR size

 

[QuietBob]

BAR0 is reported as 32768 MB on my 24 GB 7900XTX. Using the latest beta driver. Shouldn't it read 24576 MB? Unless the shared system memory is also taken into account?
IIRC it was 8196 MB on the 6600XT, i.e. the card's actual VRAM:

 

[W1zzard]

BAR0 is reported as 32768 MB on my 24 GB 7900XTX. Using the latest beta driver. Shouldn't it read 24576 MB? Unless the shared system memory is also taken into account?
IIRC it was 8196 MB on the 6600XT, i.e. the card's actual VRAM:

View attachment 283050

Bar sizes can only be power of two, so 2 4 8 16 32

 

[archie_kaos]

Hello, i'm confused if my yesterday ordered Intel Arch A750 will work with my Motherboard/CPU.

GPU-Z showed the following:



"Resizable BAR" is activated in the UEFI
"Above 4G" is also activated

The installed Graphics-Card is a Nvidia GTX 1070.

Its an old Motherboard with an old CPU. In the UEFI with the newest Bios-Update (7.30) - i can activate "Above 4G" and "Resizable BAR". The Motherboard is a Asrock X370 Killer SLI with a Ryzen 1700X.

I hope its working - so i don't need to sent back the new Intel-GPU to the Dealer. I did not know that Resizable Bar is a must have for Intel GPUs... before i ordered the Graphics Card yesterday. When it will work, i will be very happy! I hope the Arch A750 will work without any further Equipment. I know that a GTX 1070 has no Support for Resizable Bar, but i'm confused if Resizable Bar is really supported/active by my Motherboard/CPU.

Regards

Archie

 

[Macro Device]

Resizable Bar is really supported/active by my Motherboard/CPU.

Yeah, it's fully enabled.

Regardless of ReBAR state your Intel GPU will work. The problem is it will work way worse if ReBAR is off.

 

[W1zzard]

Hello, i'm confused if my yesterday ordered Intel Arch A750 will work with my Motherboard/CPU.

GPU-Z showed the following:

View attachment 307931

"Resizable BAR" is activated in the UEFI
"Above 4G" is also activated

The installed Graphics-Card is a Nvidia GTX 1070.

Its an old Motherboard with an old CPU. In the UEFI with the newest Bios-Update (7.30) - i can activate "Above 4G" and "Resizable BAR". The Motherboard is a Asrock X370 Killer SLI with a Ryzen 1700X.

I hope its working - so i don't need to sent back the new Intel-GPU to the Dealer. I did not know that Resizable Bar is a must have for Intel GPUs... before i ordered the Graphics Card yesterday. When it will work, i will be very happy! I hope the Arch A750 will work without any further Equipment. I know that a GTX 1070 has no Support for Resizable Bar, but i'm confused if Resizable Bar is really supported/active by my Motherboard/CPU.

Regards

Archie

The report suggests that you have everything enabled in BIOS correctly, so when you swap to Intel, ReBAR should activate correctly. Do let us know please once you've got the card.

 

[Mussels]

Its an old Motherboard with an old CPU. In the UEFI with the newest Bios-Update (7.30) - i can activate "Above 4G" and "Resizable BAR". The Motherboard is a Asrock X370 Killer SLI with a Ryzen 1700X.

Neither that CPU nor GPU (the 1070) support ReBar
It's only officially supported on 3000 series ryzen (excluding 3000G) and 5000 series

The motherboard supports it because it can run those newer CPUs, but I don't think anyone can tell you how well it'll work because no one's tried it.


From reports i've seen online they can in theory support it, but it entirely comes down to the motherboards BIOS as to how well it works, if at all.

 

[Macro Device]

I don't think anyone can tell you how well it'll work because no one's tried it.

With some tinkering, even Sandy Bridge can do ReBAR. His config handles it natively, or borderline natively.

 

[masterdeejay]

With some tinkering, even Sandy Bridge can do ReBAR. His config handles it natively, or borderline natively.

All CPUs that support pcie 3.0 and Uefi bios to be exact.
But not all motherboard bios can handle big BAR sizes but at least 2Gb should work on the low-end boards.
And there is some brand workstations don't allow modded bios.

I did the rebar uefi mod on a Dell T5810 (works with 8gb bar size)
https://www.techpowerup.com/forums/threads/dell-workstation-owners-club.243124/page-115

For the card i think the oldest nvidia pcie 3.0 high end cards support it (Tesla K20c - GTX780ti works), on AMD i think the GCN cards works (r9 290x 100% works).

 

[archie_kaos]

Yes, its working! And thanx for your Answers, this was my first Hardware-Updgrade in Five Years. Resizable Bar is working with my Asrock X370 Killer SLI and the old Ryzen 1700X with the newest BIOS-Update, thanx to Asrock. And i read that you can activate Resizable Bar on much older Systems with unofficial UEFI-Mods. Some People say that you need the newest CPU which is incorrect. Resizable Bar is in the PCI Express-Specs since Version 2.0. It only depends on the UEFI.



In a few Months i can Upgrade the CPU on this Board to the Ryzen 5800X3D. This is the longest lasting System-Build i ever had. Good its still ready for Upgrades. And i can play some new Blockbuster-Games tonight.

 

[Macro Device]

I did the rebar uefi mod on a Dell T5810

Nice one. My deepest XP has been with a Xeon E3-1240 V5 + H110M (patched to support both Xeons and ReBAR) + RX 580 8 GB (originally RX 480 8 GB). Benefits, though, have been negligible. About 0.5 percent higher average framerates with about 3 percent higher 1% lows.

 

[Mussels]

With some tinkering, even Sandy Bridge can do ReBAR. His config handles it natively, or borderline natively.

The problem is these boards have erratic support. Because AGESA is modular some boards have the option and it works on 5000 and 3000, but not others.
Some users on reddit have found the Ryzen 1600AF worked, but not the earlier 1600AE variant - and boards that worked with the 1600AF didn't work with a 2700x despite it being technically the same generation.

I've forgotten the dang name of it again, but you can upload your BIOS to a website and it verifies the files and shows the versions used for each CPU generation and some boards simply didn't update every one of them to the latest, so support can be crazy (hence AMD only officially supporting 3000 and 5000, as they didn't enforce this due to the problems with BIOS sizes back then)


Edit: aha!
Ryzen SMU Checker (kolos.github.io)


This is the latest BIOS for the x370 killer SLI, 7.30

Do i know what versions work with REBAR, etc? Not a clue!

This is a comparison between 6.00 and the newer 7.30, you can see summit ridge had no changes while everything else had small updates - for all we know, those smaller updates added rebar support.

 

[archie_kaos]

Do i know what versions work with REBAR, etc? Not a clue!

7.30 in my Case. And i will not downgrade it for testing - because its perfect working.

Should i downgrade for you the UEFI, Mister Big Boss?
Oh Sorry, what a terrible fault from me!
I hope such a great Moderator and cool Guy with the latest and most expensive-Stuff is not offended!

Good Bye!

 

[Mussels]

7.30 in my Case. And i will not downgrade it for testing - because its perfect working.

Should i downgrade for you the UEFI, Mister Big Boss?
Oh Sorry, what a terrible fault from me!
I hope such a great Moderator and cool Guy with the latest and most expensive-Stuff is not offended!

Good Bye!

Where did this attitude come from? At no point did I or anyone else suggest downgrading

If you're this angry over being told it's not officially supported, you're not going to have a very bad time getting help on this issue
I'm genuinely confused by you. Did you misread something?

 

[Zyll Goliat]

All CPUs that support pcie 3.0 and Uefi bios to be exact.
But not all motherboard bios can handle big BAR sizes but at least 2Gb should work on the low-end boards.
And there is some brand workstations don't allow modded bios.

I did the rebar uefi mod on a Dell T5810 (works with 8gb bar size)
https://www.techpowerup.com/forums/threads/dell-workstation-owners-club.243124/page-115

For the card i think the oldest nvidia pcie 3.0 high end cards support it (Tesla K20c - GTX780ti works), on AMD i think the GCN cards works (r9 290x 100% works).

Well for me it's working on X79 Platform with modded bios but only up to the 1gb bar size anything above that is the fubar I also have above 4g decode in my bios on Sabertooth mobo but if I turned that on I cant start my system....so there is that maybe there is some work around and I didn't tried all options but honestly benefits with the rebar on are almost negligible......

 

[masterdeejay]

Well for me it's working on X79 Platform but only up to the 1gb bar size anything above that is the fubar I also have above 4g decode in my bios on Sabertooth mobo but if I turned that on I cant start my system....so there is that maybe there is some work around and I didn't tried all options but honestly benefits with the rebar on are almost negligible......
View attachment 308331

I think that without decoding over 4g, the card cannot have a large memory address, so only 1gb works.
If the rebar is fully functional with a size of 4-8-16gb, the fps gain is a 1-5%. Depends on the card, driver, cpu, game...
It is a free boost, and i think it is most needed in cpu limited rigs, and with intel cards.

 

[Mussels]

I think that without decoding over 4g, the card cannot have a large memory address, so only 1gb works.

It is required, and once it's on only UEFI booting works - no CSM.

@Zyll Goliat that would possibly be your issue, i'm guessing you either have a non UEFI OS, or your GPU doesnt support it somehow? - it should, but you're using a motherboard with a modded BIOS and an uncommon setup, so something could just be a bug no one discovered or a setting that doesnt work

Also your systems only at PCI-E 2.0, doesn't x79 support 3.0?
Your CPU supports 3.0 as well, according to intels spec sheets

 

[Zyll Goliat]

It is required, and once it's on only UEFI booting works - no CSM.

@Zyll Goliat that would possibly be your issue, i'm guessing you either have a non UEFI OS, or your GPU doesnt support it somehow? - it should, but you're using a motherboard with a modded BIOS and an uncommon setup, so something could just be a bug no one discovered or a setting that doesnt work

Also your systems only at PCI-E 2.0, doesn't x79 support 3.0?
Your CPU supports 3.0 as well, according to intels spec sheets

Yeah sure my mobo support PCIe Gen 3 it's just because my Xeon is heavily OC via BCLK(115) then my PCIe works only on Gen 2 but either way even when is on stock settings on gen3 is the same above 4g decoding ain't working or rebar above 1g.....Now my system it is UEFI it's W11 but installed over/updated my old w10 so who knows maybe it's some problem there....but anyway no worries because everything working fine on all test and with rebar on I do have some improvements.....

 

[Mussels]

Rebar is part of the PCI-E 3 spec, so that might be the issue right there if you've disabled it to OC higher
updating from 10/11 is fine - it's whether the drive is initialised as GPT and running UEFI booting as the only criteria there.


If all these things have been tested and it doesnt help, it may be a limit of the platform since the setting was exposed by modding

 

[Zyll Goliat]

Rebar is part of the PCI-E 3 spec, so that might be the issue right there if you've disabled it to OC higher
updating from 10/11 is fine - it's whether the drive is initialised as GPT and running UEFI booting as the only criteria there.


If all these things have been tested and it doesnt help, it may be a limit of the platform since the setting was exposed by moddiNo

Well...nah Actually it's not.....it's working just fine on Gen 2....Anyway as I said I tried also with stock settings and with PCIe Gen 3 and it's totally the same thing....so there is that...

 

[Ch4vv]

Hello everyone, I have a little problem, I found this option recently and the truth is that I don't know if it will help me but I see that there is a lot of knowledge here and maybe I am not aware of something, I need help about it.
Will the BAR work with these components?
- CPU r5 3400g
- GPU rx5600xt
- MOBO b450 ds3h.
Because I have checked if the option appeared and it turns out that it does not, I have already tried certain things and it still does not appear.

 

[Klaus1189]

You need any Ryzen 5000 CPU