Resizable Bar not working.

[:D:D]

Above 4G is for when using BAR sizes typically above 1GiB since resources are limited at 4GiB.

 

[Dr. Dro]

Above 4G is for when using BAR sizes typically above 1GiB since resources are limited at 4GiB.

Yeah, but it's one of the formal requirements for Resizable BAR support.

 

[:D:D]

No, it's a requirement when the graphics aperture size doesn't fit with everything else below 4GiB addressing, it's not a requirement of resizable BAR itself.

I don't have a rebar enabled card but we can use a much older nvidia method to resize the BAR that some engineer had the foresight to include.

In this instance I'm using a 1GiB aperture (BAR1) which fits below 4GiB address space and so CSM can be enabled and 4G disabled. Technically it's resized but not using extended capability 0x15 however setting 64MiB which is also resized from the default 256MiB shows disabled so would have to ask @W1zzard what's going on there. As there is no tooltip to explain as suggested earlier, we have to guess and I would guess it maybe working on the principle of anything over 256MiB qualifies as enabled?

Note that if we set 2GiB then on my system this doesn't fit below 4GiB so to work needs above 4G decoding which means CSM disabled.

Note that the spec also notes using 32-bit BAR's and not advertising 4GiB or higher options.

Hope this helps, if not don't worry about it as likely the vast majority of people IMHO don't care.

 

[Dr. Dro]

Yes, you are right at a technical level, but it's very much an unsupported configuration, and even in that case the BAR size doesn't cover the entire VRAM. The smallest VRAM on supported hardware is 4 GB, which automatically implies the additional limitations I've mentioned earlier.

 

[W1zzard]

Technically it's resized but not using extended capability 0x15

Technically you are correct. In our context, resizable bar stands for a scenario where the BAR is sized as big as the VRAM (or bigger), and the driver makes use of this capability to optimize transfers between cpu and gpu

 

[WANLeader]

I have a TUF-RTX3080-10G-GAMING-PD Graphics card with VBIOS version 94.02.42.40.64 with a build dating back to 2020-11-26, I'm trying to enable resizeable bar. Still, it just won't work, I'm suspecting it's an outdated VBIOS, but when I attempt to update the VBIOS with Asus' RTX3080_V5 file it just says "Your graphics card doesn't need to update VBIOS!". In my motherboard settings, I have enabled Above 4G Decode, and have resizable bar set to "auto" as there is no "enabled" option. CSM is disabled as well, so I don't know. I did a clean install of NVidia drivers with DDU and everything. I have an ASUS TUF B550M-Plus WiFi (Zaku Edition) which had been flashed back in June of this year. The last BIOS build for the motherboard came out in April this year and is still the most up-to-date.

What more can I do in an attempt to remedy this?

Have the exact same GPU. The motherboard that the Case came with is an MSI X570-A Pro and when I updated the first time to the latest BIOS the Resizable BAR Feature would enable but the BIOS when save and closing would mention, "You have made No Changes to the BIOS..." and would restart as normal. I downloaded the firmware file again, (The same one), and this time, the firmware file fixed the issue and also had it enabled by default! Sure enough, nVidia control panel confirmed it was enabled, and that, Good Sir, is my advice. Update the motherboard again with the same file. Very weird issue that well I have to say, I have two PC's that did this. The other is an Asus ROG Strix X570-E Gaming Wi-Fi ii board. I thought it was my GPU. NOPE! Good luck!!

 

[mattpf_]

Can anybody help me?
I activated the resizable bar in my motherboard's BIOS, but gpuz still says it is disabled.

B450M Stell Legend
Ryzen 5 5600x
Rtx 3050 MSI Gaming x

 

[Dr. Dro]

Can anybody help me?
I activated the resizable bar in my motherboard's BIOS, but gpuz still says it is disabled.

B450M Stell Legend
Ryzen 5 5600x
Rtx 3050 MSI Gaming x

If that info in MSI's application is about your motherboard, its BIOS is 3 years out of date. Current version is 8.01, download that and flash. Once that's done, then re-enable Resizable BAR support and make sure your computer is booting in UEFI, not CSM mode. If CSM is enabled, Resizable BAR will not work because that's BIOS emulation. Also, ensure you have the latest drivers that Nvidia released.

 

[WANLeader]

I have a TUF-RTX3080-10G-GAMING-PD Graphics card with VBIOS version 94.02.42.40.64 with a build dating back to 2020-11-26, I'm trying to enable resizeable bar. Still, it just won't work, I'm suspecting it's an outdated VBIOS, but when I attempt to update the VBIOS with Asus' RTX3080_V5 file it just says "Your graphics card doesn't need to update VBIOS!". In my motherboard settings, I have enabled Above 4G Decode, and have resizable bar set to "auto" as there is no "enabled" option. CSM is disabled as well, so I don't know. I did a clean install of NVidia drivers with DDU and everything. I have an ASUS TUF B550M-Plus WiFi (Zaku Edition) which had been flashed back in June of this year. The last BIOS build for the motherboard came out in April this year and is still the most up-to-date.

What more can I do in an attempt to remedy this?

I loaded the latest bios, rebooted and this was still a problem. BIOS would enable REBAR but windows (nvidia control panel) said it was not enabled. Leading me to attempt the same VBIOS you did.

In a last ditch effort I decided to reinstall the EXACT same motherboard BIOS a second time. To my shock, IT WAS FIXED IN WINDOWS. Glory Hallelujah! I suppose it would be worth trying on your board?!

Can anybody help me?
I activated the resizable bar in my motherboard's BIOS, but gpuz still says it is disabled.

B450M Stell Legend
Ryzen 5 5600x
Rtx 3050 MSI Gaming x

Reinstall the same BIOS. Mine didn't enable REBAR the first time around.

 

[mattpf_]

If that info in MSI's application is about your motherboard, its BIOS is 3 years out of date. Current version is 8.01, download that and flash. Once that's done, then re-enable Resizable BAR support and make sure your computer is booting in UEFI, not CSM mode. If CSM is enabled, Resizable BAR will not work because that's BIOS emulation. Also, ensure you have the latest drivers that Nvidia released.

Can you help me with the bios?
wich version i install
4.60? or beta

 

[VulkanBros]

 

[Klemc]

Should i disable ReBar on my Prime z390M-Plus, aka bios update introduced this option, it's an older platform.

A bios trick by Asus/Nvidia !!

 

[Hyderz]

Should i disable ReBar on my Prime z390M-Plus, aka bios update introduced this option, it's an older platform.

A bios trick by Asus/Nvidia !!

I have mine enabled, unless I do test I’m noticing anything different but you know free performance is free

 

[Dr. Dro]

Can you help me with the bios?
wich version i install
4.60? or beta

8.01 beta, that agesa isn't even the newest, AsRock hasn't supported this board nearly as well as they should have given its popularity

Should i disable ReBar on my Prime z390M-Plus, aka bios update introduced this option, it's an older platform.

A bios trick by Asus/Nvidia !!

Klem, why would you want it OFF?

 

[simiqz]

Hey everyone

Also having problems, I have enabled the resize bar in bios and I'm pretty sure I need to update my vbios so the resize bar will actually work. However I am not good with PCs and have no idea what vbios to download could anyone help me? I have added screenshots to make it easier if anyone could help me, thanks in advance!

 

[meatwar]

*EVGA GeForce RTX 3090, 3080, 3070, and 3060 Ti graphics cards require a VBIOS update available through EVGA Precision X1
EVGA - Articles - Resizable BAR

 

[Dr. Dro]

Hey everyone

Also having problems, I have enabled the resize bar in bios and I'm pretty sure I need to update my vbios so the resize bar will actually work. However I am not good with PCs and have no idea what vbios to download could anyone help me? I have added screenshots to make it easier if anyone could help me, thanks in advance!

GPU-Z says ReBAR is not enabled in your motherboard BIOS settings and this is more than likely the case. Either way: this is the latest VBIOS for your graphics card:

EVGA RTX 3070 VBIOS

8 GB GDDR6, 1500 MHz GPU, 1750 MHz Memory

www.techpowerup.com

Use nvflash without any overrides, it should work. Just nvflash64 (vbios file name).rom

Can you fill in your system specs? It'll help us figure out what's going on. Cheers and welcome to TPU