Wired internet suddenly extremely slow

I've been complaining for some time on slow response from browsers and other things connected, but never suspected connection speed. Finally checked it and it turned up 1-5 Mbit/s. On all other computers I have 200-300.

Unplugged the cable and plugged it into a windows computer, got 250 Mbit/s. So not cable.

Plugged an ethernet adapter to USB, still the same, a couple of Mbit/s. So, not network card.

Found advice on turning ASPM off in grub file. Added GRUB_CMDLINE_LINUX="pcie_aspm=off pcie_port_pm=off" to it, did the update-grub, restarted, still no change.

Have done the apt update and apt upgrade. What might be the problem?Thanks

lsb_release -a

No LSB modules are available.Distributor ID: UbuntuDescription:    Ubuntu 22.04.4 LTSRelease:    22.04Codename:   jammy

inxi -Nn

Network:  Device-1: Intel 82578DM Gigabit Network driver: e1000e  IF: enp0s25 state: down mac: 6c:62:6d:c4:b7:1a  Device-2: Realtek RTL8153 Gigabit Ethernet Adapter type: USB    driver: r8152  IF: enxa0cec864e1a3 state: up speed: 1000 Mbps duplex: full    mac: a0:ce:c8:64:e1:a3  IF-ID-1: vpn state: unknown speed: N/A duplex: N/A mac: N/A

sudo lshw -C network

*-network                        description: Ethernet interface       product: 82578DM Gigabit Network Connection       vendor: Intel Corporation       physical id: 19       bus info: pci@0000:00:19.0       logical name: enp0s25       version: 05       serial: 6c:62:6d:c4:b7:1a       capacity: 1Gbit/s       width: 32 bits       clock: 33MHz       capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation       configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=6.5.0-35-generic firmware=0.12-2 latency=0 link=no multicast=yes port=twisted pair       resources: irq:24 memory:f0400000-f041ffff memory:f0425000-f0425fff ioport:1100(size=32)  *-network       description: Ethernet interface       physical id: 6       bus info: usb@2:1.8       logical name: enxa0cec864e1a3       serial: a0:ce:c8:64:e1:a3       size: 1Gbit/s       capacity: 1Gbit/s       capabilities: ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation       configuration: autonegotiation=on broadcast=yes driver=r8152 driverversion=v1.12.13 duplex=full firmware=rtl8153a-4 v2 02/07/20 ip=192.168.10.102 link=yes multicast=yes port=MII speed=1Gbit/s

Hardware is:

• Hewlett-Packard HP Compaq 8100 Elite SFF PC
• 8,0 GiB RAM,
• Intel® Core™ i5 CPU 650 @ 3.20GHz × 4