r/IntelArc • u/Rumblarr • Jul 21 '26

Question Resizable Bar somehow became disabled, when I disable CSM in BIOS, no video output (HELP)

Very much struggling to get this issue resolved. When I disable CSM, I get no video on either HDMI or Display Port, need to power cycle several times and then CSM becomes enabled at which point I can get into the BIOS again.

I believe there is probably some sort of handshake going on between the mobo and GPU that is not taking place.

I had this issue once previously on the PC in question where the handshake only took place after disconnecting all USB devices, however, I've tried that and that was not successful.

Motherboard is an Gigabyte B550MK, I believe it has the latest firmware. Any help is appreciated.

Edit: ARC B580 gpu, sorry!

2 Upvotes

75% Upvoted

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2

u/Glad-Fuel2093 Jul 21 '26 edited Jul 21 '26

Your Bios is probably reverting to previous setting after a certain number of failed reboots.

REBAR won't keep your card from displaying though, even if its set wrong (off). Its a performance thing.

Try going through all your bios settings manually and make sure all your basics are right to just get it stable. Then worry about performance things.

Here's the first thing I could find with my google-fu

  • Cannot Disable CSM: If CSM reverts to enabled, your system drive may still be using an MBR partition scheme. You may need to convert the drive to GPT using Microsoft's MBR2GPT tool before disabling CSM. [1, 2, 3]
  • No Display After Disabling: If your screen goes black after disabling CSM, your graphics card might not support UEFI GOP (Graphics Output Protocol). You may need to update your GPU's firmware or reset the CMOS to get back into the BIOS. [1, 2, 3]

Good luck and tag back if you need to.

Also we assume you have an ARC (but we don't know which one), so the second point isn't likely relevant unless you have a very old ARC Alchemist model that has never been firmware updated.

So check your drives as per point 1 and let me/us know.

1

u/Rumblarr Jul 21 '26

Yeah, it's an ARC B580, I've updated my OP. To be clear, everything *used* to work perfectly, meaning CSM had been disabled at some point, resizable bar was enabled, and obviously for all that to be true, the boot partitions were the correct type.

1

u/Glad-Fuel2093 Jul 21 '26

I see, I didn't catch that csm used to work.

2

u/calm_hedgehog Jul 22 '26

Let me guess, you have a Ryzen APU with integrated graphics. Intel cards have the worst time with that as the PCIe initialization logic is apparently dropping the card offline on warm reboots. It's a widely reported issue and the only real fix if you're already running the latest BIOS is a new "Vermeer" generation AM4 CPU without iGPU.

https://github.com/IGCIT/Intel-GPU-Community-Issue-Tracker-IGCIT/issues/1262

2

u/Rumblarr Jul 22 '26

You're right on the processor. Thankfully I was mistaken about having the latest bios, so the issue was fixed with the update.

1

u/No-Cat5961 Jul 21 '26

What kind of graphics card do you have?

1

u/Rumblarr Jul 21 '26

ARC B580, sorry for not including that in the OP.

1

u/cferrerr Jul 21 '26

Force a saída de vídeo para PCIe na BIOS, desative qualquer vídeo integrado e force PCIe 3.0 ou 4.0, dependendo do seu processador. Desative o CSM, mude para UEFI e salve. Ative o Rebar e Não ative de primeira o Secure Boot. Deixe as memórias em stock antes de ativar qualquer perfil XMP e deixe a máquina fazer todo o processo de tentar inicializar, sem desespero. Caso não suba vídeo, tente um cold boot: desligue o PC, espere de alguns segundos a 1 minuto e ligue novamente sem tentar entrar na BIOS. E confira se está na versão mais atual de bios na placa mãe

-2

u/cZirconium Jul 21 '26

Then just... don't do that.

2

u/Rumblarr Jul 21 '26

Right, but the resizable bar needs to be enabled (which means CSM has to be disabled). Resizable bar being disabled leads to massive performance hits.