GPU Error (6 Beeps) on HP Z620 Workstation

[Daintyleaf]

Greetings

I am having issues with my HP Z620 Workstation when using an NVIDIA RTX 2060 GPU. Upon powering on the system, I often encounter a 6-beep error, which I understand indicates a graphics card initialization failure. Here are the details:

Symptoms:

During a cold boot, the system beeps 6 times, and the screen stays black. If I perform a restart, the system sometimes boots normally, and the GPU functions perfectly in Windows (e.g., rendering, stress tests). Enabling Fast Boot prevents the beeps but results in a black screen for several seconds before Windows loads, if at all on the first try.

Things I tried:

Reseated the GPU and checked all connections. Updated GPU drivers and ensured the system BIOS is on the latest version. Tested different boot options (Fast Boot vs. Regular Boot). 

The GPU is working as expected under load, so the issue appears to occur only during the POST/boot initialization phase. I suspect it may be a compatibility issue between the Z620’s BIOS and the RTX 2060. Im looking into installing a modified BIOS that has improved UEFI support and better PCIe compatibility. Here is the GitHub of the project: https://github.com/bibikalka1/HP_Z420_Z620_Z820_BOOTBLOCK2013_BIOS_mod.

I would really appreciate any guidance or solutions.

[Daintyleaf · Accepted solution]

Appreciate all the help, everyone... not. 🙃 I managed to fix the issue myself by upgrading to Windows 11, despite my system being officially unsupported. Turns out the enhanced UEFI compatibility layer in Windows 11 resolved the 6-beep POST issue. 

Thanks for nothing! 

(let me know if any of you need further clarification on what I did)