Comment 0 for bug 1937926

I am using the Realtek 8821C PCIE Wifi driver that is provided in the Additional drivers app of Ubuntu. When I connect to a 2.4 ghz network, the internet speed is very slow, it rarely goes above 4mbps. But the driver works fine when connected to a 5ghz network, easily reaching speeds of over 80mbps. I don't think it is a problem of my wifi router because in Windows OS running on the same laptop, I mostly get speeds of around 40mbps when connected to the 2.4 ghz network.

1. What is the full computer model number?
Ans: HP Laptop 15s-eq0500AU.
2. If you update your BIOS to the newest version following the guide here, does this change anything?
Ans: No.
3. Regarding your wireless Access Point (WAP):
3o. What frequency are you using (2.4GHz, 5GHz, etc.)?
Ans: 2.4 GHz
3p. If you change frequency does it change anything?
Ans: Yes, speed is good in 5ghz
4. Does another wireless device tested with the WAP have the same problem as the hardware you initially reported with?
Ans: No.
5. What is the distance of the wireless device from the WAP?
Ans: 6 metre
6. What is the number and type of obstructions between your device and the WAP?
Ans: 2
6a. If you bring the device close to the WAP and eliminate obstructions, does this change anything?
Ans: No
7. Does the issue occur with different WAPs?
Ans: Yes
8. Is it a regression (i.e. did the problem happen in a prior Ubuntu release)? If so, what release specifically did it last work with? If you do not know, could you please test for this in the earliest release of Ubuntu that is supported as per Ubuntu Releases?
Ans: I don't know if it is a regression and I cannot test for this in another release of Ubuntu.
9. Does this problem occur in the newest mainline kernel following https://wiki.ubuntu.com/Kernel/MainlineBuilds? Please mention what specific version of the mainline kernel you tested with in your report.
Ans: Kernel version: 5.11.0-25-generic

ProblemType: Bug
DistroRelease: Ubuntu 21.04
Package: linux-image-5.11.0-25-generic 5.11.0-25.27
ProcVersionSignature: Ubuntu 5.11.0-25.27-generic 5.11.22
Uname: Linux 5.11.0-25-generic x86_64
ApportVersion: 2.20.11-0ubuntu65.1
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: soumadeepsarkar1 1797 F.... pulseaudio
 /dev/snd/controlC0: soumadeepsarkar1 1797 F.... pulseaudio
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Sun Jul 25 10:11:55 2021
InstallationDate: Installed on 2021-07-02 (23 days ago)
InstallationMedia: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
MachineType: HP HP Laptop 15s-eq0xxx
ProcEnviron:
 LANGUAGE=en_IN:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_IN
 SHELL=/bin/bash
ProcFB: 0 amdgpudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.11.0-25-generic root=UUID=2d1ce438-fd55-446d-8d61-e2d579055204 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-5.11.0-25-generic N/A
 linux-backports-modules-5.11.0-25-generic N/A
 linux-firmware 1.197.2
SourcePackage: linux
UpgradeStatus: Upgraded to hirsute on 2021-07-02 (22 days ago)
dmi.bios.date: 05/13/2021
dmi.bios.release: 15.42
dmi.bios.vendor: AMI
dmi.bios.version: F.42
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: 86FD
dmi.board.vendor: HP
dmi.board.version: 99.41
dmi.chassis.type: 10
dmi.chassis.vendor: HP
dmi.chassis.version: Chassis Version
dmi.ec.firmware.release: 99.41
dmi.modalias: dmi:bvnAMI:bvrF.42:bd05/13/2021:br15.42:efr99.41:svnHP:pnHPLaptop15s-eq0xxx:pvr:rvnHP:rn86FD:rvr99.41:cvnHP:ct10:cvrChassisVersion:
dmi.product.family: 103C_5335KV HP Notebook
dmi.product.name: HP Laptop 15s-eq0xxx
dmi.product.sku: 440L6PA#ACJ
dmi.sys.vendor: HP