[SOLVED] Qualcomm QCNCM865 slow internet speed

ExileSoul · 2026-08-23 16:06:18

My configuration, base installation with KDE-Plasma this morning

=== KERNEL ===
7.1.9-arch1-2
=== CARTE PCI ===
06:00.0 Network controller: Qualcomm Technologies, Inc WCN785x Wi-Fi 7(802.11be) 320MHz 2x2 [FastConnect 7800] (rev 01)
	DeviceName: RTL8111EPV
	Subsystem: Foxconn International, Inc. High Band Simultaneous Wireless Network Adapter
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupts: MSI(X) routed to IRQ 132-147
	IOMMU group: 24
	Region 0: Memory at fc200000 (64-bit, non-prefetchable) [size=2M]
	Capabilities: <access denied>
	Kernel driver in use: ath12k_wifi7_pci
	Kernel modules: ath12k_wifi7

=== FIRMWARE VERSION ===
[    4.691447] ath12k_wifi7_pci 0000:06:00.0: BAR 0 [mem 0xfc200000-0xfc3fffff 64bit]: assigned
[    4.691483] ath12k_wifi7_pci 0000:06:00.0: enabling device (0000 -> 0002)
[    4.691529] ath12k_wifi7_pci 0000:06:00.0: Wi-Fi 7 Hardware name: wcn7850 hw2.0
[    4.692078] ath12k_wifi7_pci 0000:06:00.0: MSI vectors: 16
[    5.262580] ath12k_wifi7_pci 0000:06:00.0: chip_id 0x2 chip_family 0x4 board_id 0xff soc_id 0x40170200
[    5.262584] ath12k_wifi7_pci 0000:06:00.0: fw_version 0x1103006c fw_build_timestamp 2026-03-06 09:10 fw_build_id QC_IMAGE_VERSION_STRING=WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3
[    5.463904] ath12k_wifi7_pci 0000:06:00.0 wlo1: renamed from wlan0
=== LIEN ACTUEL ===
Connected to XX:XX:XX:XX:XX:XX (on wlo1)
	SSID: MonReseau
	freq: 5220.0
	RX: 189909408 bytes (178364 packets)
	TX: 63580543 bytes (94703 packets)
	signal: -43 dBm
	rx bitrate: 907.4 MBit/s 80MHz HE-MCS 9 HE-NSS 2 HE-GI 1 HE-DCM 0
	tx bitrate: 960.7 MBit/s 80MHz HE-MCS 9 HE-NSS 2 HE-GI 0 HE-DCM 0
	bss flags: short-slot-time
	dtim period: 1
	beacon int: 100
=== STATION DUMP ===
Station XX:XX:XX:XX:XX:XX (on wlo1)
	authorized:	yes
	authenticated:	yes
	associated:	yes
	preamble:	long
	WMM/WME:	yes
	MFP:		no
	TDLS peer:	no
	inactive time:	122 ms
	rx bytes:	189909408
	rx packets:	178364
	tx bytes:	63580543
	tx packets:	94703
	tx retries:	0
	tx failed:	0
	beacon loss:	0
		beacon rx:	8820
	rx drop misc:	21
	signal:  	-43 [-48, -44] dBm
	signal avg:	0 dBm
	beacon signal avg:	-41 dBm
	tx bitrate:	960.7 MBit/s 80MHz HE-MCS 9 HE-NSS 2 HE-GI 0 HE-DCM 0
	tx duration:	0 us
	rx bitrate:	907.4 MBit/s 80MHz HE-MCS 9 HE-NSS 2 HE-GI 1 HE-DCM 0
	rx duration:	0 us
	last ack signal:-53 dBm
	avg ack signal:	-53 dBm
	DTIM period:	1
	beacon interval:100
	short slot time:yes
	connected time:	912 seconds
	associated at [boottime]:	22.716s
	associated at:	1787499761745 ms
	current time:	1787500673472 ms

=== linux-firmware version ===
linux-firmware 20260810-2

I did a speedtest

Retrieving speedtest.net configuration...
Testing from Videotron Ltee (24.157.178.18)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Rogers Wireless (Ottawa, ON) [234.23 km]: 39.202 ms
Testing download speed................................................................................
Download: 44.81 Mbit/s
Testing upload speed......................................................................................................
Upload: 13.22 Mbit/s

This is not what i used to have on Windows, i used to get around 800mbps average and no latency. I did the test before swaping to arch linux. And my phone gets 400mbps. I have tried for hours and hours and can't figure this one out.

The only thing i can say on this issue is i saw that my rx bitrate drops to 6mbps sometimes. I am new to all of arch linux side so im not event sure what that means hehe.

If anyone have any idea on what to try let me know.

Last edited by ExileSoul (2026-08-23 20:36:54)

ExileSoul · 2026-08-23 19:50:10

After countless hours i found out that changing

in /etc/NetworkManager/conf.d/iwd.conf

I added this.

[device]
wifi.backend=iwd

instead of wpa_supplicant make it worked. Now i have my 800mbps on speedtest.. I do not know why it works.

Last edited by ExileSoul (2026-08-23 19:51:10)

seth · 2026-08-23 20:23:20

https://wiki.archlinux.org/title/Networ … Fi_backend
NetworkManager log extensively, you can check your older system journals for NM or wpa_supplicant complaints.

Please always remember to mark resolved threads by editing your initial posts subject - so others will know that there's no task left, but maybe a solution to find.
Thanks.

Arch Linux

#1 2026-08-23 16:06:18

[SOLVED] Qualcomm QCNCM865 slow internet speed

#2 2026-08-23 19:50:10

Re: [SOLVED] Qualcomm QCNCM865 slow internet speed

#3 2026-08-23 20:23:20

Re: [SOLVED] Qualcomm QCNCM865 slow internet speed

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