HP ProBook x360 435 G7

Hardware	PCI/USB ID	Working?
GPU	`1002:1636`	Yes
HDMI audio	`1002:1637`	Yes
Audio	`1022:15e3`	Yes
Microphone	`1022:15e3`	Yes
Wireless	`10ec:c822`	Yes
Bluetooth	`0bda:b00c`	Yes
Accelerometer	`1022:15e4`	Yes
Touchpad	I2C	Yes
Touchscreen	I2C	Yes
SD-card reader	`10ec:522a`	Yes
Webcam	`04f2:b6af`	Yes
Fingerprint reader	`06cb:00df`	Yes

The HP ProBook x360 435 G7 is a 13.3" convertible with an AMD Ryzen 4000 Renoir APU (Ryzen 3 4300U, Ryzen 5 4500U, or Ryzen 7 4700U). Other parts also differ between configurations, see #Variants.

Accessibility

The following keys work while the HP logo is shown:

Esc: startup menu, also offers the firmware update
F3: third-party option ROM management
F9: boot device menu
F10: firmware setup
F11: system recovery

The firmware setup is graphical, with the tabs Main, Security, Advanced and UEFI Drivers and an Item Specific Help pane on the right. It can be operated completely with the keyboard. HP provides an interactive BIOS simulator showing every menu, which can be used to find a setting before changing it on the device.

Firmware

fwupd lists the system firmware as an UEFI capsule device (ESRT), but HP does not publish firmware for this model on the LVFS, so fwupdmgr get-updates reports no updates.

HP does not provide update files for Linux. The firmware can update itself, either from the network or from a file on the EFI system partition.

Recovery

The firmware keeps 21MiB big update and recovery images on the EFI system partition at \EFI\HP\DEVFW\firmware.bin and \EFI\Hewlett-Packard\BIOS\ with the subdirectories Current and New. These directories are used for BIOS recovery. If a firmware update fails, the firmware's Crisis Recovery Mode searches the internal drive and USB media for a compatible image. If none is found, copy S80_XXYYZZ.bin from the SoftPaq to \EFI\HP\BIOS\Current on a FAT32-formatted USB stick and power on the laptop. This is described in Bios Flash.htm, which is included in every BIOS SoftPaq.

Available versions

HP lists all released firmware versions of this model (platform ID 8735, ROM family S80) with checksums in 8735.xml. The installed version and the embedded controller revision are shown by dmidecode -t 0. Release notes are linked from HP's support page, the SoftPaqs HP BIOS and System Firmware (S80).

Updating from the network

connect laptop to a LAN
enter bios by pressing ESC on boot
check for BIOS updates
follow instructions for upgrading or roll back

Updating from a local file

The Windows SoftPaq (spXXXXXX.exe) is a self-extracting archive that contains the firmware image S80_XXYYZZ.bin. Extract it with 7zip and copy the image to the EFI system partition as \EFI\HP\DEVFW\firmware.bin (the name is case-insensitive):

$ 7z x spXXXXXX.exe -osoftpaq
# cp softpaq/S80_XXYYZZ.bin esp/EFI/HP/DEVFW/firmware.bin

where esp is the mount point of the EFI system partition, e.g. /boot.

Connect the AC adapter, reboot, press Esc at the HP logo and select Update System and Supported Device Firmware (or F10 > Main > Update System BIOS > Update System and Supported Device Firmware Using Local Media). Flashing starts immediately, without showing the versions or asking for confirmation, so make sure the right image is in place beforehand.

Suspend

The firmware only supports S3, which is the default (deep in /sys/power/mem_sleep). Suspend to idle is not supported

In S3 the laptop draws roughly 0.5 W (2 % of the battery in 95 minutes).

Wake-ups at low battery

When the battery is almost empty (observed at about 7 % and below with BIOS 01.15.00), the firmware wakes the laptop from S3 a few seconds after every suspend. If something suspends it again, e.g. a power manager that treats a wake-up with closed lid as unintended, or a critical battery action of suspend, the laptop loops through short suspend/resume cycles until the battery is completely drained.

The wake-up cannot be blocked from the operating system. Therefore do not use suspend as action for a critical battery level. Power off (or hibernate) at a level above the wake-up threshold instead. Note that UPower with the default CriticalPowerAction=Auto suspends when hibernation is not available, for example:

/etc/UPower/UPower.conf.d/50-critical.conf

[UPower]
PercentageCritical=10.0
PercentageAction=8.0
CriticalPowerAction=PowerOff

Battery

The kernel does not offer a charge threshold for this battery (charge_control_end_threshold is missing in /sys/class/power_supply/BAT0/). Charging can only be limited in the firmware, Advanced > Power Management Options > Battery Health Manager. With Maximize my battery health the embedded controller reports the limited (to 80%) capacity as full charge capacity.

Power consumption

Measured on battery with an otherwise idle system (kernel 7.2.9, BIOS 01.25.00, Ryzen 7 4700U, 1920x1080 panel). The embedded controller reports no current_now while discharging and updates charge_now only in steps of about 35 mAh, so the values are calculated from the times of these steps over at least 20 minutes. Expect an error of a few tenths of a watt.

State	Power
Display off	2.4 W
Display on, brightness 0 %	4.4 W
Display on, brightness 100 %	4.4 W
Display on, brightness 0 %, Wi-Fi power saving on	2.7 W
All cores busy, `powersave` governor (1.4 GHz)	9 W
All cores busy, `schedutil` governor (2.0 GHz)	10–13 W
All cores busy, `schedutil` with boost (about 3.0 GHz, 85–90 °C)	35–42 W

Note

The brightness makes no measurable difference, but a switched-on display costs about 2 W. AMDGPU does not enable panel self refresh on this laptop with kernel 7.2, even with amdgpu.dcfeaturemask=0xa. It works with 7.1 and linux-lts 6.18, see drm/amd issue 5993.
Wi-Fi power saving saves about 1.8 W, but slows down bursty traffic, see #Wi-Fi.
The CPU only offers the frequencies 1.4, 1.7 and 2.0 GHz plus boost via acpi-cpufreq. amd_pstate is not available, because the firmware does not provide CPPC. The powersave governor therefore pins the CPU to 1.4 GHz. Tools like auto-cpufreq^AUR select it on battery by default.

Fan control

The embedded controller controls the fan on its own and does it well. The fan stays off at idle and light load most of the time (e.g. at 47 °C) and spins up under load. No driver or daemon is needed.

The fan can neither be read nor controlled from Linux. There is no lm_sensors device, hp-wmi creates pwm1_enable, but reading and writing to it fails, ACPI defines no fan device, and finally there is no platform profile (/sys/firmware/acpi/platform_profile is missing).

The only setting is the firmware option Fan Always on while on AC Power. Its current value can be read with hp-bioscfg:

$ cat "/sys/class/firmware-attributes/hp-bioscfg/attributes/Fan Always on while on AC Power/current_value"

Wi-Fi

With power saving enabled, the Realtek RTL8822CE (rtw88) loses much of its throughput for bursty traffic such as video streaming, where the player fills its buffer, waits and then downloads again. Measured with downloads of 10 MB after 8 seconds of idle (median of 10, kernel 7.2.9, 5 GHz, -57 dBm):

Power saving	Throughput	Time to first byte
off	9.3 MB/s	0.34 s
on	3.3 MB/s	0.80 s

Short pings after idle periods are hardly affected, but streams stall. Disable power saving, e.g. with NetworkManager:

/etc/NetworkManager/conf.d/wifi-powersave.conf

[connection]
wifi.powersave = 2

To test without NetworkManager, use iw dev wlan0 set power_save off.

Speakers

The bottom-firing speakers sound thin and tinny without processing. Measured with a calibrated microphone at ear position in a small room, their response falls by 10 dB at about 330 Hz and by 20 dB at about 190 Hz, nothing is left below 120 Hz, and a resonance at about 950 Hz sticks out by 9 dB. With pink noise the level varies by -6 to +13 dB.

An easyeffects output preset following the Easy Effects guide for notebook speakers, with an added cut for the resonance, brings the response between 500 Hz and 10 kHz to within about ±3 dB, removes the honk at 1 kHz and raises the low mids by 5 to 13 dB. Chain, in this order:

Plugin	Settings
Filter	High-pass, 100 Hz, slope x3 (36 dB/oct), IIR
Bass Enhancer	amount +24 dB, harmonics 10, scope 250 Hz
Filter	Bell, 950 Hz, gain -8 dB, quality 0.9
Multiband Compressor	Linear Phase, input gain -4 dB, output gain +5 dB, five bands (see below)
Stereo Tools	stereo base 0.25
Limiter	Herm Thin, oversampling Half x4/16 bit, threshold -1 dB, lookahead 4 ms, attack 2 ms, release 8 ms

Band	Range	Threshold	Ratio	Attack / release	Knee	Makeup
1	< 320 Hz	-16 dB	5	150 / 300 ms	-12 dB	-6 dB
2	320–750 Hz	-24 dB	3	150 / 200 ms	-9 dB	+9 dB
3	750–1700 Hz	-27 dB	4	100 / 150 ms	-9 dB	-2 dB
4	1.7–6 kHz	-24 dB	3	100 / 150 ms	-9 dB	+4 dB
5	> 6 kHz	-24 dB	4	80 / 120 ms	-9 dB	0 dB

Note

Use Linear Phase in the multiband compressor; Modern leaves dips at every split frequency.
The Bass Enhancer's harmonics fall into the range the speakers can still play, which is where the fuller sound comes from. Frequencies below the high-pass would only waste headroom.
Load the preset only for the speakers by using Easy Effects' autoload for the Speakers route of the internal sound card and a flat preset for Headphones and other outputs.
The values depend on the surface the laptop stands on, since the speakers fire downwards. The measurement was done on a desk. Subjectively, it also greatly improves sound quality when not on a desk.

Tablet mode

This laptop has a sensor built in to detect if it is in tablet mode.

When in tablet mode, the keyboard is disabled. See Tablet PC#Automatic rotation for auto-rotation.

Fingerprint reader

Some configurations have a Synaptics fingerprint reader (06cb:00df, shown by lsusb), which is supported by fprint. fwupdmgr get-devices lists two sub-devices for it, Prometheus and its IOTA Config. Two firmware issues may prevent it from working; both can be solved with fwupd:

If fprintd-enroll does not find the reader, update its firmware with fwupdmgr, possibly after enabling the lvfs-testing remote (see fwupdmgr(1)).
If fprintd-enroll finds the reader but fails with enroll-unknown-error, the installed fwupd version likely has a bug that prevents updating the Prometheus IOTA Config. fwupd 1.6.x was affected, 1.5.9 worked: temporarily install the older version and update the firmware with it. Because of a checksum mismatch it may be necessary to download the firmware manually from fwupd.org. Afterwards, upgrade the system again to replace the outdated fwupd.
Resetting the reader's own storage may also help: enable Security > Fingerprint Reset on Reboot in the firmware setup. Make sure no installed operating system requires a fingerprint before doing so.

Fingerprint reader after suspend

If a verification is running while the laptop suspends (e.g. a screen locker that scans in the background), fprintd may afterwards refuse every request with Device was already claimed. Restarting fprintd.service fixes it; better stop the scan before suspending.
The sensor calibrates itself whenever it is reset. Since libfprint 1.94.10 the driver resets the reader every time fprintd starts or the reader reappears (MR 533). libfprint disables USB persist for the reader, so after resume the kernel often re-enumerates it and fprintd probes it again; otherwise fprintd, which exits when idle, is started again on demand. Either way the reset happens 0.3 to 1.2 seconds after the lid is opened. If a finger rests on the sensor at that moment, every following touch fails. The debug log then shows Finger is now on the sensor and 0.1 s later off, without Fingerprint image capture complete. Wait two or three seconds after opening the lid before touching the sensor.

Keyboard

Fn lock, Fn+Shift

With BIOS 1.04.02 and 1.05.00, Fn lock and Fn+Shift+key combinations did not work; rolling back to 1.03.00 fixed it. The problem no longer occurs with BIOS 01.15.00 and later, so update the firmware instead.

Replacing the keyboard

The keyboard is fastened to the top cover with many plastic rivets, which have to be removed to take it out. Either drill them out or cut off their protruding heads with a knife. Replacing the keyboard this way works. Afterwards the keyboard is slightly less stable, because the removed rivets no longer press it against the top cover, but it remains well usable without replacing the rivets.

Touchpad

Touchpad unresponsive

With BIOS 1.03.00 the touchpad sometimes stopped working. This no longer occurs with BIOS 01.15.00 and later, so update the firmware. On older firmware, reboot or restart hid to fix it:

# rmmod i2c_hid_acpi
# rmmod i2c_hid
# modprobe i2c_hid_acpi
# modprobe i2c_hid

This can be executed at boot for a quick fix, e.g. via a systemd service.

Touchpad lags while charging

While the battery is charging, the ELAN touchpad reacts with a visible delay. After movements the pointer keeps moving for a moment after the finger has stopped. On battery, and on AC with a fully charged battery, it behaves normally. The delay is added by the touchpad firmware and cannot be tuned away in software.

Rubber feet

The two long rubber feet on the bottom cover are glued on and come off after a few years, as they are constantly warmed by the laptop.

Aftermarket replacement feet with matching dimensions are flat, while the mounting surface on the bottom cover is ridged, with an angled edge that is higher in the middle (roughly /\ in cross-section), so the flat strips cannot be glued on properly.

Replacing the whole bottom cover works instead. Bottom covers pulled from the ProBook 435 G10 are sold as compatible with G7 to G10 and fit this laptop. Since the feet are attached the same way, they may come off again after some years.

Function keys

Key	Visible?¹	Marked?²	Effect
`Fn+F1`	Yes	Yes	`XF86Display`
`Fn+F3`	Yes	Yes	`XF86MonBrightnessDown`
`Fn+F4`	Yes	Yes	`XF86MonBrightnessUp`
`Fn+F5`	Yes	Yes	`XF86AudioMute`
`Fn+F6`	Yes	Yes	`XF86AudioLowerVolume`
`Fn+F7`	Yes	Yes	`XF86AudioRaiseVolume`
`Fn+F8`	Yes	Yes	`XF86AudioMicMute`
`Fn+F10`	Yes	Yes	`Insert`
`Fn+F11`	Yes	Yes	`XF86RFKill`, sent by the Wireless hotkeys device (`wireless_hotkey`, ACPI `HPQ6001`)
`Fn+F12`	Yes	Yes	`XF86Launch8` (`KEY_F17`)
`Fn+Up`	Yes	Yes	`Prior` (Page Up)
`Fn+Down`	Yes	Yes	`Next` (Page Down)
`Fn+Left`	Yes	Yes	`Home`
`Fn+Right`	Yes	Yes	`End`
`Fn+w`	Yes	No	`Pause`
`Fn+e`	Yes	No	`Insert`
`Fn+r`	Yes	No	`Break` (`Ctrl+Pause`)
`Fn+s`	Yes	No	`Print` (`KEY_SYSRQ`, same as the `Print` key)
`Fn+c`	Yes	No	`Scroll_Lock`

The key is visible to xev and similar tools.
The physical key has a symbol on it, which describes its function.

F1 to F12 without Fn emit the normal function keys; Fn+F2 and Fn+F9 have no symbol and also emit F2 and F9.

Variants

According to the HP datasheet, the following parts differ between configurations:

Part	Options
CPU	Ryzen 3 4300U (4 cores, 2.7–3.7 GHz), Ryzen 5 4500U (6 cores, 2.3–4.0 GHz), Ryzen 7 4700U (8 cores, 2.0–4.1 GHz)
Wi-Fi and Bluetooth	Intel Wireless-AC 9260, Intel Wi-Fi 6 AX200, Realtek 802.11ac (RTL8822CE)
Display	13.3" FHD IPS touch screen with 250 nits (45 % NTSC), 400 nits (72 % NTSC) or 1000 nits (72 % NTSC) with HP Sure View privacy screen
Storage	128 GB M.2 SATA SSD, 256 GB to 512 GB M.2 NVMe SSD
Memory	2 SO-DIMM slots, DDR4-3200, up to 16 GB¹
Camera	720p HD or HD and IR (user-facing), optional 5 MP world-facing camera
Keyboard	optional backlight

HP specifies up to 16 GB; 32 GB (2 × 16 GB) are verified to work, larger modules are untested.

The PCI/USB IDs in the hardware table are from a Ryzen 7 4700U model with the Realtek Wi-Fi card.