Resizable BAR cannot be enabled with the Arc B580

[huksuk]

Hello. I have a Biostar H410MH (version 6.1) motherboard, an i3-10100 processor, and an Arc B580 graphics card. My operating system is Windows 10 22H2, installed on a GPT disk. My motherboard is set to UEFI mode, and CSM is disabled. Above 4G Decoding is enabled, and the Resize BAR setting is set to Auto (there is no Enabled option in the system; only Disabled and auto are available). Despite this, GPU-Z shows Above 4G Decoding enabled and Resize BAR is disabled.
Additionally, the Intel Graphics Software also indicates that Resize BAR is disabled. 

The even stranger part is that I didn't have any of these issues with my old graphics card. The RX 550 didn't support Resizable BAR, yet GPU-Z showed both Above 4G Decoding and Resizable BAR as enabled.

[JohnM_Intel]

Thank you for providing such detailed information regarding your concern.

First, regarding the RX 550 comparison, the RX 550 does not natively support Resizable BAR. Therefore, the ReBAR reading shown in GPU-Z for that card may have been inaccurate or misleading. GPU-Z's ReBAR detection can sometimes produce unexpected results depending on the graphics card and platform, so that reading should not be used as a reliable baseline.

The Arc B580 reading you are seeing now is the one we should focus on.

Regarding the Arc B580 showing Resizable BAR as disabled, your BIOS configuration appears correct on the surface, with UEFI mode enabled, CSM disabled, GPT partitioning, and Above 4G Decoding enabled.

However, I would like to be transparent that the H410 chipset is a 10th-generation Comet Lake platform, and ReBAR support on H410 motherboards can depend heavily on how the motherboard manufacturer implemented the feature in the BIOS firmware.

Since the Auto setting on your Biostar H410MH does not provide an explicit Enabled option, it is possible that the motherboard firmware is not fully supporting or allocating the required resources for ReBAR with a newer discrete GPU such as the Arc B580. The lack of an explicit ReBAR option may indicate a platform or BIOS limitation.

That said, I recommend working through the following steps:

• First, please check if there is a newer BIOS version available for your Biostar H410MH v6.1. Some H410 boards received BIOS updates that improved PCIe BAR handling for newer GPUs. You can check here: https://www.biostar.com.tw/app/en/mb/introduction.php?S_ID=1010
• Next, please review the Intel Arc Graphics Quick Start Guide, which outlines the Resizable BAR requirements and supported configurations: https://www.intel.com/content/www/us/en/support/articles/000091128/graphics.html
• Also, the message from Intel Graphics Software indicating Resizable BAR is disabled is actually expected behavior on platforms where the firmware cannot confirm ReBAR status. You can find more details on this here: https://www.intel.com/content/www/us/en/support/articles/000090862.html
• Finally, if the latest BIOS does not add an explicit "Enabled" option for Resize BAR, I would recommend reaching out to Biostar support directly to confirm whether the H410MH v6.1 can support Resizable BAR for discrete GPUs and whether a future BIOS update can address this for the Arc B580.

[huksuk · Accepted solution]

I contacted Biostar’s support team, and they provided me with a BIOS version they had developed themselves that enables Resizable BAR support for NVIDIA graphics cards, even though the feature has not yet been officially released. I updated my BIOS to this version, and Resizable BAR was successfully enabled.

[JohnM_Intel]

Thank you for letting me know that the Biostar Support Team provided you with a BIOS update. I’m glad to hear that you are now able to enable Resizable BAR.

Since the issue has been resolved, you may click the “Accept as Solution” button to mark the case as resolved.

Thank you for your cooperation.

[Refupickudeker]

Can you send me the bios version to my email! 

Email : [email protected]

[huksuk]

I'm sorry. I cannot share something that Biostar hasn't released. You should contact Biostar support; they will be able to help you.

[Refupickudeker]

Sorry, but I didn't got any response from Biostar. That's why I was trying to get help from others. And I thought you could help!

[AlHill]

@Refupickudeker   You really need to deal with biostar regarding bios support for their motherboard.

https://www.biostar-usa.com/app/en-us/support/support.php

Doc (not an Intel employee or contractor)
[Success breeds complacency. Complacency breeds failure. (Andy Grove)]

[Refupickudeker]

There is no response from Biostar. Can anyone here help?

[AlHill]

@Refupickudeker   It may be the case that this is somwhat of a holiday weekend.

Doc (not an Intel employee or contractor)
[Success breeds complacency. Complacency breeds failure. (Andy Grove)]

[Refupickudeker]

Thanks, guys, for the help. Biostar did provide me the custom bios, and my system has rebar enabled now. I will look forward to you guys regarding intel gpu related issues in future. ( As im a new intel gpu user )