I can independently confirm this issue on my system. **My hardware:** - Dedicated GPU: Sapphire AMD (PCI ID: 1002:7590) - Integrated GPU: AMD Radeon RX Vega 6 (PCI ID: 1002:1636) - Distribution: Linux Mint 22.3 - Kernel: 7.0.0-42-generic - Monitor: Acer HA220Q (1920x1080, HDMI)
**Problem:** After the firmware update from 0ubuntu3.3 to 0ubuntu3.4 on November 5, 2026, my monitor showed No Signal during normal boot. I had to use `nomodeset` to start Linux, but GPU hardware acceleration stopped working and OpenGL used llvmpipe software rendering. **Kernel errors:** ```text failed to load ucode DMCUB(0x3F) LOAD_IP_FW failed Wait for DMUB auto-load failed: 3 DMCUB error - collecting diagnostic data ``` **Successful workaround:** I downgraded `linux-firmware-amd-graphics` to version 0ubuntu3.3 and rebuilt initramfs for all installed kernels. After completely powering off and restarting, Linux Mint booted normally without `nomodeset`. Both AMD GPUs now use the amdgpu driver, and OpenGL hardware acceleration works correctly. I can confirm that version 0ubuntu3.3 works on my hardware, while version 0ubuntu3.4 causes the display failure. Please investigate this firmware regression and provide a corrected update. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2173041 Title: black screen after upgrading linux-firmware-amd-graphics to 0ubuntu3.4 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-firmware-amd-graphics/+bug/2173041/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
