No display after disabling CSM for ReBar.(ARC A750)

[Ashfaq]

I disabled CSM to turn on ReBar.But after disabling CSM,display does not post,no keyboard or mouse .I disconnected GPU and tried to post with igpu and it works fine but no display after plugging in gpu again.My drives ar GPT and bios is UEFI.

CPU:5600G

Motherboard:Gigabyte DS3H B550M,revision 1.5(bios:f3d)

GPU:ARC A750

[n_scott_pearson]

That's really odd, considering that the A750 definitely provides a UEFI Video Driver in its Op-ROM.

...S

[Jean_Intel]

Hello Ashfaq,

Thank you for posting in the Intel Communities. We are more than happy to help you solve the problem when booting your system after disabling CSM.

To better help you, we would like to ask for the following

• Did you make any other BIOS changes besides the CSM option?
• If CSM is enabled, does the Intel Arc graphics work as expected?
• Does the issue remain when testing different monitors?
• Are you able to enter the BIOS menu when booting into the Operating System while you have CSM enabled?
• What is the Intel Arc A750 graphics card model? (Limited edition, Sparkle, Gunnir, MSI, AsRock, Acer)

This is quite a strange behavior since Intel has confirmed that the Intel Arc graphics should work with the Compatibility Support Module (CSM), as this is the recommendation when using Intel Arc A-series graphics. UEFI boot mode must be Enabled

Best regards

Jean O.

Intel Customer Support Technician

[Ashfaq]

1. I have made no changes except disabling CSM.
2. When CSM is enabled the card works as expected.

3. I have tested on 3 different monitors and the issue remains the same.

4. When CSM is enabled I can enter BIOS normally.(If I disable CSM I have to pull out CMOS to reset BIOS and than                  monitor,keyboard,mouse responses and CSM gets enabled again).

5. I am using Intel ARC A750 Limited Edition.

Hope it helps.

[Jean_Intel]

Hello Ashfaq,

Thank you for the information provided. We understand that there are no issues with CMS being enabled, and you can enter the BIOS menu, but as soon as you enable CSM, there is no keyboard, monitor, mouse, or response after disabling CSM. Based on this information, we will proceed to look into this matter internally and will post back as soon as we have more details.

Best regards

Jean O.

Intel Customer Support Technician

[Jean_Intel]

Hello Ashfaq,

After looking into this issue, we would recommend you disable CSM so ReBAR can be enabled as you have tried, but this time try a clean Operating System installation. Once you test this, let us know if there video during the OS installation process.

Finally, we would recommend you test your Intel Arc A750 graphics card on a different system in case you don't have any video during the Operating System installation process.

Best regards

Jean O.

Intel Customer Support Technician

[Ashfaq]

Thanks!

I will try that and let you know as soon as possible.

[Jean_Intel]

Hello Ashfaq,

We are checking in your thread to see if you have been able to test our recommendation. Let us know whether or not the issue is solved.

Best regards

Jean O.

Intel Customer Support Technician

[afsar]

I have same issue.Tried reinstalling Windows, no luck.I tried using my TV as a monitor and it resolved the problem. With the TV, I could disable CSM, enable ReBar, and everything worked seamlessly.So is it a monitor issue?

[Jean_Intel]

Hello afsar,

Thank you for sharing your experience in the thread. We are glad to hear that you were able to disable CMS and enable Rebar after testing using your TV and that the system worked seamlessly after changing the display device. This indicates that the graphics card is working fine, and the problem seems to lie with the monitor. We recommend checking with the monitor OEM for further assistance.

Best regards

Jean O.

Intel Customer Support Technician

[Jean_Intel]

Hello Ashfaq,

Unfortunately, we will proceed to close this thread as we have not heard back from you. As we mentioned before, we recommend trying a clean Operating System installation, as well as testing the Intel Arc A750 graphics card on a different system in case you don't have any video during the Operating System installation process. If you have any other questions, submit a new thread, as this one will no longer be monitored.

Best regards

Jean O.

Intel Customer Support Technician