network card only works with 100 Mbit

    Failure to set Gbit speeds is normally caused by bad cables, a problem switch/hub port, or (occasionally but not often) hardware issues. It is possible to force Gbit operations and full-duplex mode etc. using "ethtool" but if auto-detection fails this is unlikely to solve the problem.

    Please share "pastekodi" URL so we can look for issues in the boot log and see what NIC is actually being used.

    how do I get the URL of pastekodi? but I type lspci and saw there that there is a 00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (17) I219-V (rev 11)

    If you run "pastekodi" with a network connection (even 100Mbit) it will output a URL which you can copy/paste here. We want to see the boot log included in paste.

    No output means the submission failed (silently). Check for bad cables, bad switch ports, dirty ethernet sockets. Everyone swears their $1 Ethernet cable is fine; until it isn't fine.

    Quote from Voosjey

    I now have cat 8 cables, but the data speed is just 2 MB/s, the data goes through two switches, once a Netgear GS16E and then a DELL N1548

    Hi, did you checked if not wiring/hardware issue? Tried to boot another OS and checked the speed? If not, try to boot a linux os like Ubuntu from USB stick, search for "Ventoy" and "Ubuntu ISO". In a few minutes you can prepare an USB stick to boot directly different iso images.