Nothing showing until login screen
 

Hello, I just resurrected an old PC where I've installed Ubuntu 21.10 and Windows 10, dual boot with 2 separated hard disks.

When I use my Dell D6000, the monitors are without signal until the Ubuntu login appears. I can't see the BIOS messages and GRUB, so it's very hard to choose the OS.

If I use another display with HDMI I can see everything in the right way.

Both D6000 firmware and Display Link drivers are up to date.

Can anybody help me? Thanks in advance!

No one can help me? :(