Video - works. This system has 2 video cards: Intel i915 & NVIDIA Quadro K2100M. I didn't test the NVIDIA one, but I suppose it works.

Sound - works

Sound recording with built-in microphone - works

Builtin Webcam - works (tested with Cheese Webcam Booth)

Wireless - doesn't work. Apparently there is no driver loaded.

Ethernet - didn't test, but should work, the eth0 device appears in ifconfig

Bluetooth - seems to work. I could pair to an Android smartphone, but I couldn't transfer files.

Touchpad - works

Multimedia keys - screen brightness keys work; sound volume control keys work

USB 2.0 - works

Battery - after disconnecting the power plug, the battery meter showed ~4h left

Suspend - entered suspend successfully. resumed successfully

00:00.0 Host bridge [0600]: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller [8086:0c04] (rev 06)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller [8086:0c01] (rev 06)
	Kernel driver in use: pcieport
00:02.0 VGA compatible controller [0300]: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06)
	Subsystem: Hewlett-Packard Company Device [103c:1909]
	Kernel driver in use: i915
00:14.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI [8086:8c31] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: xhci_hcd
00:16.0 Communication controller [0780]: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 [8086:8c3a] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: mei_me
00:16.3 Serial controller [0700]: Intel Corporation 8 Series/C220 Series Chipset Family KT Controller [8086:8c3d] (rev 04)
	Subsystem: Hewlett-Packard Company Device [103c:1909]
	Kernel driver in use: serial
00:19.0 Ethernet controller [0200]: Intel Corporation Ethernet Connection I217-LM [8086:153a] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: e1000e
00:1a.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 [8086:8c2d] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: ehci-pci
00:1b.0 Audio device [0403]: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller [8086:8c20] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: snd_hda_intel
00:1c.0 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 [8086:8c10] (rev d4)
	Kernel driver in use: pcieport
00:1c.4 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #5 [8086:8c18] (rev d4)
	Kernel driver in use: pcieport
00:1c.6 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #7 [8086:8c1c] (rev d4)
	Kernel driver in use: pcieport
00:1c.7 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #8 [8086:8c1e] (rev d4)
	Kernel driver in use: pcieport
00:1d.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 [8086:8c26] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: ehci-pci
00:1f.0 ISA bridge [0601]: Intel Corporation QM87 Express LPC Controller [8086:8c4f] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: lpc_ich
00:1f.2 RAID bus controller [0104]: Intel Corporation 82801 Mobile SATA Controller [RAID mode] [8086:282a] (rev 04)
	Subsystem: Hewlett-Packard Company Device [103c:1909]
	Kernel driver in use: ahci
00:1f.3 SMBus [0c05]: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller [8086:8c22] (rev 04)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK106GLM [Quadro K2100M] [10de:11fc] (rev a1)
	Subsystem: Hewlett-Packard Company Device [103c:1909]
	Kernel driver in use: nouveau
01:00.1 Audio device [0403]: NVIDIA Corporation GK106 HDMI Audio Controller [10de:0e0b] (rev ff)
	Kernel driver in use: snd_hda_intel
5c:00.0 Network controller [0280]: Intel Corporation Centrino Advanced-N 6235 [8086:088e] (rev 24)
	Subsystem: Intel Corporation Centrino Advanced-N 6235 AGN [8086:4060]
5d:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5249 PCI Express Card Reader [10ec:5249] (rev 01)
	Subsystem: Hewlett-Packard Company ZBook 15 [103c:1909]
	Kernel driver in use: rtsx_pci

Slot:	00:00.0
Class:	Host bridge [0600]
Vendor:	Intel Corporation [8086]
Device:	Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller [0c04]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	06

Slot:	00:01.0
Class:	PCI bridge [0604]
Vendor:	Intel Corporation [8086]
Device:	Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller [0c01]
Rev:	06

Slot:	00:02.0
Class:	VGA compatible controller [0300]
Vendor:	Intel Corporation [8086]
Device:	4th Gen Core Processor Integrated Graphics Controller [0416]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	Device [1909]
Rev:	06

Slot:	00:14.0
Class:	USB controller [0c03]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family USB xHCI [8c31]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04
ProgIf:	30

Slot:	00:16.0
Class:	Communication controller [0780]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family MEI Controller #1 [8c3a]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04

Slot:	00:16.3
Class:	Serial controller [0700]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family KT Controller [8c3d]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	Device [1909]
Rev:	04
ProgIf:	02

Slot:	00:19.0
Class:	Ethernet controller [0200]
Vendor:	Intel Corporation [8086]
Device:	Ethernet Connection I217-LM [153a]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04

Slot:	00:1a.0
Class:	USB controller [0c03]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family USB EHCI #2 [8c2d]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04
ProgIf:	20

Slot:	00:1b.0
Class:	Audio device [0403]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset High Definition Audio Controller [8c20]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04

Slot:	00:1c.0
Class:	PCI bridge [0604]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family PCI Express Root Port #1 [8c10]
Rev:	d4

Slot:	00:1c.4
Class:	PCI bridge [0604]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family PCI Express Root Port #5 [8c18]
Rev:	d4

Slot:	00:1c.6
Class:	PCI bridge [0604]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family PCI Express Root Port #7 [8c1c]
Rev:	d4

Slot:	00:1c.7
Class:	PCI bridge [0604]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family PCI Express Root Port #8 [8c1e]
Rev:	d4

Slot:	00:1d.0
Class:	USB controller [0c03]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family USB EHCI #1 [8c26]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04
ProgIf:	20

Slot:	00:1f.0
Class:	ISA bridge [0601]
Vendor:	Intel Corporation [8086]
Device:	QM87 Express LPC Controller [8c4f]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04

Slot:	00:1f.2
Class:	RAID bus controller [0104]
Vendor:	Intel Corporation [8086]
Device:	82801 Mobile SATA Controller [RAID mode] [282a]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	Device [1909]
Rev:	04

Slot:	00:1f.3
Class:	SMBus [0c05]
Vendor:	Intel Corporation [8086]
Device:	8 Series/C220 Series Chipset Family SMBus Controller [8c22]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	04

Slot:	01:00.0
Class:	VGA compatible controller [0300]
Vendor:	NVIDIA Corporation [10de]
Device:	GK106GLM [Quadro K2100M] [11fc]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	Device [1909]
Rev:	a1

Slot:	01:00.1
Class:	Audio device [0403]
Vendor:	NVIDIA Corporation [10de]
Device:	GK106 HDMI Audio Controller [0e0b]
Rev:	ff
ProgIf:	ff

Slot:	5c:00.0
Class:	Network controller [0280]
Vendor:	Intel Corporation [8086]
Device:	Centrino Advanced-N 6235 [088e]
SVendor:	Intel Corporation [8086]
SDevice:	Centrino Advanced-N 6235 AGN [4060]
Rev:	24

Slot:	5d:00.0
Class:	Unassigned class [ff00]
Vendor:	Realtek Semiconductor Co., Ltd. [10ec]
Device:	RTS5249 PCI Express Card Reader [5249]
SVendor:	Hewlett-Packard Company [103c]
SDevice:	ZBook 15 [1909]
Rev:	01

Bus 002 Device 002: ID 8087:8000 Intel Corp. 
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8008 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 005: ID 04f2:b3ed Chicony Electronics Co., Ltd 
Bus 003 Device 004: ID abcd:1234 Unknown 
Bus 003 Device 002: ID 138a:003f Validity Sensors, Inc. VFS495 Fingerprint Reader
Bus 003 Device 006: ID 8087:07da Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub