Slower download speed compared to Windows on Ubuntu 20.04

I have just installed Ubuntu 20.04 and I am facing a pretty big issue. My download speeds are really low compared to the Windows 10 that I have installed on dual-boot setup.

This is the speed I'm getting in Windows.

And this is what I'm getting in Ubuntu.

My network adapter is Lenovo RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller.

I have tried changing the DNS options but that doesn't help.

Device is a Lenovo Y700-15ISK Laptop.

Output lshw:

*-network DISABLED
       description: Wireless interface
       product: QCA9377 802.11ac Wireless Network Adapter
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:08:00.0
       logical name: wlp8s0
       version: 30
       serial: cc:b0:da:b7:60:65
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath10k_pci driverversion=5.4.0-29-generic firmware=WLAN.TF.2.1-00021-QCARMSWP-1 latency=0 link=no multicast=yes wireless=IEEE 802.11
       resources: irq:142 memory:94000000-941fffff
  *-network
       description: Ethernet interface
       product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
       vendor: Realtek Semiconductor Co., Ltd.
       physical id: 0
       bus info: pci@0000:09:00.0
       logical name: enp9s0
       version: 15
       serial: c8:5b:76:3e:55:50
       size: 1Gbit/s
       capacity: 1Gbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=r8168 driverversion=8.048.00-NAPI duplex=full ip=192.168.100.2 latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s
       resources: irq:131 ioport:3000(size=256) memory:94304000-94304fff memory:94300000-94303fff

Also, the ifconfig shows a lot of dropped RX packages that are increasing as we speak:

Solution 1:

From the comments...

• 20.04, booting from the 5.4.0-29 kernel netted very poor ethernet download speeds

• tried the r8168-dkms driver with no improvement in download speeds

• updating to a 5.6.11 kernel and the download speeds were back to normal, but the Nvidia/CUDA stuff broke, no surprise, and will need an update

• rebooted to the 5.4.0-29 kernel and confirmed that Nvidia works again, and download speeds reverted

• purged the 5.6.11 kernel packages

• no newer 5.4.0 kernels were available to install

• booted to an older 5.4.0-26 kernel and download speeds were still low

• Summary... the 5.4.0 kernels don't work well with this (version 15) r8168/r8169 ethernet card

Update #1:

Removed nvidia driver and installed nvidia-dkms-440 from their repository and then installed 5.5.19 and the driver built just fine on this kernel version. And now both my internet and my graphics card are working.