Asus Prime B350M-K User manual

Motherboard
PRIME B350M-K

ii
E12609
First Edition
February 2017
Copyright © 2017 ASUSTeK COMPUTER INC. All Rights Reserved.
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iii
Contents
Safety information ...................................................................................... iv
About this guide ......................................................................................... iv
Package contents ....................................................................................... vi
PRIME B350M-K specications summary................................................ vi
Chapter 1 : Product introduction
1.1 Before you proceed ..................................................................... 1-1
1.2 Motherboard overview................................................................. 1-1
1.3 Central Processing Unit (CPU) ................................................. 1-10
1.4 System memory ......................................................................... 1-12
Chapter 2 : BIOS information
2.1 Managing and updating your BIOS ............................................ 2-1
2.2 BIOS setup program .................................................................... 2-5
2.3 Exit menu.................................................................................... 2-10
Appendix
Notices.......................................................................................................A-1
ASUS contact information .......................................................................A-5

iv
Safety information
Electrical safety
• To prevent electrical shock hazard, disconnect the power cable from the electrical outlet
before relocating the system.
• When adding or removing devices to or from the system, ensure that the power cables
for the devices are unplugged before the signal cables are connected. If possible,
disconnect all power cables from the existing system before you add a device.
• Before connecting or removing signal cables from the motherboard, ensure that all
power cables are unplugged.
• Seek professional assistance before using an adapter or extension cord. These devices
could interrupt the grounding circuit.
• Ensure that your power supply is set to the correct voltage in your area. If you are not
sure about the voltage of the electrical outlet you are using, contact your local power
company.
• If the power supply is broken, do not try to x it by yourself. Contact a qualied service
technician or your retailer.
Operation safety
• Before installing the motherboard and adding components, carefully read all the manuals
that came with the package.
• Before using the product, ensure all cables are correctly connected and the power
cables are not damaged. If you detect any damage, contact your dealer immediately.
• To avoid short circuits, keep paper clips, screws, and staples away from connectors,
slots, sockets and circuitry.
• Avoid dust, humidity, and temperature extremes. Do not place the product in any area
where it may be exposed to moisture.
• Place the product on a stable surface.
• If you encounter technical problems with the product, contact a qualied service
technician or your retailer.
About this guide
This user guide contains the information you need when installing and conguring the
motherboard.
How this guide is organized
This guide contains the following parts:
• Chapter 1: Product introduction
This chapter describes the features of the motherboard and the new technology it
supports. It includes descriptions of the switches, jumpers, and connectors on the
motherboard.
• Chapter 2: BIOS information
This chapter discusses changing system settings through the BIOS Setup menus.

v
Where to nd more information
Refer to the following sources for additional information and for product and software
updates.
1. ASUS websites
The ASUS website provides updated information on ASUS hardware and software
products. Refer to the ASUS contact information.
2. Optional documentation
Your product package may include optional documentation, such as warranty yers,
that may have been added by your dealer. These documents are not part of the
standard package.
Conventions used in this guide
To ensure that you perform certain tasks properly, take note of the following symbols used
throughout this manual.
DANGER/WARNING: Information to prevent injury to yourself when
completing a task.
CAUTION: Information to prevent damage to the components when
completing a task
IMPORTANT: Instructions that you MUST follow to complete a task.
NOTE: Tips and additional information to help you complete a task.
Typography
Bold text Indicates a menu or an item to select.
Italics Used to emphasize a word or a phrase.
<Key> Keys enclosed in the less-than and greater-than sign
means that you must press the enclosed key.
Example: <Enter> means that you must press the Enter or
Return key.
<Key1> + <Key2> + <Key3> If you must press two or more keys simultaneously, the key
names are linked with a plus sign (+).

vi
PRIME B350M-K specications summary
(continued on the next page)
Package contents
Check your motherboard package for the following items.
Motherboard ASUS PRIME B350M-K motherboard
Cables 2 x Serial ATA 6.0 Gb/s cables
Accessories 1 x I/O shield
1 x M.2 screw package
Application DVD 1 x Support DVD
Documentation 1 x User Manual
If any of the above items is damaged or missing, contact your retailer.
CPU
AM4 socket for AMD Ryzen™ / 7th Generation A-series / Athlon™ processors
Supports CPU up to 8 cores*
* Due to CPU limitation, CPU cores supported vary by processor.
** Refer to www.asus.com for AMD CPU support list.
Chipset AMD B350 chipset
Memory
AMD Ryzen™ processors:
2 x DIMMs, max. 32GB, DDR4 3200(O.C.)/2933(O.C.)/2666/2400/2133 MHz, ECC
and non-ECC, un-buffered memory
AMD 7th Generation A-series / Athlon™ processors:
2 x DIMMs, max. 32GB, DDR4 2400/2133 MHz, non-ECC un-buffered memory
Dual-channel memory architecture
* Refer to www.asus.com for the latest Memory QVL (Qualied Vendors List).
Graphics
Integrated AMD Radeon™ R Series Graphics in the 7th Generation A-series APU
Multi-VGA output support: DVI-D, and D-Sub ports
- Supports DVI-D with maximum resolution of 1920 x 1200 @60Hz
- Supports D-Sub with maximum resolution of 1920 x 1200 @60Hz
- Maximum shared memory of 2048 MB
Expansion
slots
AMD Ryzen™ processors:
1 x PCI Express 3.0/2.0 x16 slot (max. @x16 mode)
AMD 7th Generation A-series / Athlon™ processors:
1 x PCI Express 3.0/2.0 x16 slot (max. @x8 mode)
AMD B350 Chipset:
2 x PCI Express 2.0 x1 slots
LAN Realtek®8111H Gigabit LAN controller
Audio
Realtek® ALC 887-VD2 8-Channel High Denition Audio CODEC
* Use a chassis with HD audio module in the front panel to support an 8-channel audio
output.
USB
AMD Ryzen™ / 7th Generation A-series / Athlon™ processors
- 4 x USB 3.1 Gen 1 ports (4 ports at back panel)
AMD B350 Chipset:
- 2 x USB 3.1 Gen 1 ports ( 2 ports at mid-board)
- 6 x USB 2.0/1.1 ports ( 2 ports at back panel, 4 ports at mid-board)

vii
PRIME B350M-K specications summary
(continued on the next page)
Storage
AMD B350 Chipset
- 4 x Serial ATA 6.0 Gb/s connectors with RAID 0, RAID 1 and RAID 10 support
AMD Ryzen™ processors:
- 1 x M.2 socket 3 with M Key, Type 2242/2260/2280 (PCIe 3.0 x4 and SATA
modes) storage devices support
AMD 7th Generation A-series / Athlon™ processors:
- 1 x M.2 socket 3 with M Key, Type 2242/2260/2280 (SATA modes) storage
devices support
ASUS unique
features
Dependable Stability
ASUS 5X PROTECTION III
- ASUS SafeSlot Core: Fortied PCIe Slot prevents damage
- ASUS LANGuard: Protects against LAN surges, lightning strikes and static-
electricity discharges!
- ASUS Overvoltage Protection: World-class circuit-protecting power design
- ASUS Stainless-Steel Back I/O: 3X corrosion-resistance for greater durability!
- ASUS DIGI+ VRM: 6 Phase digital power design
Superb performance
UEFI BIOS
- Most advanced options with fast response time
Easy PC DIY
Safe motherboard mounting
- Component-free areas to minimize damage risk
Q-Design
- ASUS Q-DIMM
- ASUS Q-Slot
UEFI BIOS EZ Mode
- featuring friendly graphics user interface
- ASUS CrashFree BIOS 3
- ASUS EZ Flash 3
ASUS Quiet
Thermal
Solution
Quiet Thermal Design:
- Stylish Fanless Design: Chipset Heat-sink solution
- ASUS Fan Xpert
Rear panel
I/O ports
1 x PS/2 keyboard port (purple)
1 x PS/2 mouse port (green)
1 x DVI-D port
1 x D-Sub port
1 x LAN (RJ-45) port
2 x USB 2.0/1.1 ports
4 x USB 3.1 Gen 1 ports
3 x Audio jacks support 8-channel audio output

viii
PRIME B350M-K specications summary
Internal
connectors
1 x USB 3.1 Gen 1 connector supports additional 2 USB 3.1 Gen 1 ports
2 x USB 2.0/1.1 connectors support additional 4 USB 2.0/1.1 ports
1 x M.2 socket 3 for M Key and type 2242/2260/2280 devices
4 x SATA 6.0Gb/s connectors
1 x COM connector
1 x CPU Fan connector
1 x Chassis Fan connector
1 x Front panel audio connector
1 x 24-pin EATX power connector
1 x 8-pin EATX 12V power connector
1 x 2-pin Clear CMOS header
1 x S/PDIF out connector
1 x Speaker connector
1 x System panel connector
BIOS features
128 Mb Flash ROM, UEFI AMI BIOS, PnP, DMI3.0, WfM2.0, SM BIOS 3.0,
ACPI 6.1, Multi-language BIOS, ASUS EZ Flash 3, ASUS CrashFree BIOS 3,
My Favorites, Last Modied log, F12 PrintScreen, ASUS DRAM SPD (Serial
Presence Detect) memory information, F6 Qfan Control
Manageability WfM 2.0, DMI 3.0, WOL by PME, PXE
Support DVD
Drivers
ASUS utilities
ASUS Update
Anti-virus software (OEM version)
OS support Windows®10 (64-bit)
Form factor uATX form factor: 8.9” x 8.7” (22.6 cm x 22.1 cm)
Specications are subject to change without notice.

ASUS PRIME B350M-K 1-1
Product introduction
1
1.1 Before you proceed
Take note of the following precautions before you install motherboard components or change
any motherboard settings.
• Unplug the power cord from the wall socket before touching any component.
• Before handling components, use a grounded wrist strap or touch a safely grounded
object or a metal object, such as the power supply case, to avoid damaging them due
to static electricity.
• Before you install or remove any component, ensure that the ATX power supply is
switched off or the power cord is detached from the power supply. Failure to do so
may cause severe damage to the motherboard, peripherals, or components.
Unplug the power cord before installing or removing the motherboard. Failure to do so
can cause you physical injury and damage motherboard components.
PRIME B350M-K
PCIEX16
PCIEX1_1
PCIEX1_2
SPEAKER
CLRTC
F_PANEL
SPDIF_OUT
USB56USB34 USB3_12
AAFP
COM
EATXPWR
CPU_FAN
CHA_FAN
BATTERY
Super
I/O
ALC
887
Realtek
8111H
DIGI
+VRM
22.6cm(8.9in)
AMD®
B350
DDR4 DIMM_A1 (64bit, 288-pin module)
SOCKET AM4
2280 2260 2242
M.2 (SOCKET3)
DDR4 DIMM_B1 (64bit,288-pin module)
AUDIO
KBMS
LAN_USB3_34
USB12
USB3_56
22.1cm(8.7in)
128Mb
BIOS
SATA6G_3
SATA6G_4
SATA6G_1 SATA6G_2
LANGuard
EATX12V
DVI VGA
1 42 23
1
679 8
1
1
5
15
10111214 13
16
1.2 Motherboard overview
Place this
side towards
the rear of the
chassis

1-2 Chapter 1: Product introduction
1.2.1 Layout contents
Connectors/Jumpers/Slots/LED Page
1. ATX power connectors (24-pin EATXPWR, 8-pin EATX12V) 1-2
2. CPU and chassis fan connectors (4-pin CPU_FAN, 4-pin CHA_FAN) 1-2
3. AMD AM4 CPU socket 1-3
4. DDR4 DIMM slots 1-3
5. M.2 Socket 3 1-3
6. AMD B350 SATA 6.0Gb/s ports (SATA6G_1~4) 1-3
7. System panel connector (10-1 pin PANEL) 1-4
8. Speaker connector (4-pin SPEAKER) 1-4
9. USB 3.1 Gen 1 connector (20-1 pin USB3_12) 1-4
10. USB 2.0 connectors (10-1 pin USB34,56) 1-4
11. Clear RTC RAM (2-pin CLRTC) 1-5
12. Serial port connector (10-1 pin COM) 1-5
13. Digital audio connector (4-1 pin SPDIF_OUT) 1-5
14. Front panel audio connector (10-1 pin AAFP) 1-5
15. PCI Express 2.0 x1 slots 1-6
16. PCI Express 3.0/ 2.0 x16 slot 1-6
1. ATX power connectors (24-pin EATXPWR, 8-pin EATX12V)
These connectors are for ATX power supply plugs. The power supply plugs are
designed to t these connectors in only one orientation. Find the proper orientation and
push down rmly until the connectors completely t.
• We recommend that you use an EATX 12V Specication
2.0-compliant power supply unit (PSU) with a minimum of 300W
power rating. This PSU type has 24-pin and 8-pin power plugs.
• DO NOT forget to connect the 4-pin/8-pin ATX +12V power plug.
Otherwise, the system will not boot up.
• We recommend that you use a PSU with higher power output
when conguring a system with more power-consuming devices
or when you intend to install additional devices. The system may
become unstable or may not boot up if the power is inadequate.
• If you are uncertain about the minimum power supply
requirement for your system, refer to the Recommended
Power Supply Wattage Calculator at http://support.asus.com/
PowerSupplyCalculator/PSCalculator.aspx?SLanguage=en-us for
details.
EATX12V
+12V DC
+12V DC
+12V DC
+12V DC
GND
GND
GND
GND
EATXPWR
PIN 1
PIN 1
GND
+5 Volts
+5 Volts
+5 Volts
-5 Volts
GND
GND
GND
PSON#
GND
-12 Volts
+3 Volts
+3 Volts
+12 Volts
+12 Volts
+5V Standby
Power OK
GND
+5 Volts
GND
+5 Volts
GND
+3 Volts
+3 Volts
2. CPU and chassis fan connectors (4-pin CPU_FAN, 4-pin CHA_FAN)
Connect the fan cables to the fan connectors on the motherboard, ensuring that the
black wire of each cable matches the ground pin of the connector.

ASUS PRIME B350M-K 1-3
CPU_FAN
CPU FAN PWM
CPU FAN IN
CPU FAN PWR
GND
CHA_FAN
GND
CHA FAN PWR
CHA FAN IN
CHA FAN PWM
Do not forget to connect the fan cables to the fan
connectors. Insufcient air ow inside the system may
damage the motherboard components. These are not
jumpers! Do not place jumper caps on the fan connectors!
The CPU_FAN connector supports a CPU fan of
maximum 1A (12 W) fan power.
5. M.2 socket 3
This socket allows you to install M.2 (NGFF) SSD modules.
M.2(SOCKET3)
• This socket supports M Key and 2242/2260/2280 storage devices.
• Due to CPU limitation, M.2 socket supported varies by processor. Refer to the
specications summary table for more details.
4. DDR4 DIMM slots
Install 2 GB, 4 GB, 8 GB, and 16 GB unbuffered ECC and non-ECC DDR4 DIMMs into
these DIMM sockets.
For more details, refer to System memory.
3. AMD AM4 CPU socket
This motherboard comes with an AMD AM4 socket designed for AMD Ryzen™ / 7th
Generation A-series / Athlon™ processors.
For more details, refer to Central Processing Unit (CPU).
6. AMD B350 SATA 6.0Gb/s ports (7-pin SATA6G_1~4)
These ports connect to SATA 6.0 Gb/s hard disk drives via SATA
6.0 Gb/s signal cables.
GND
RSATA_TXP
RSATA_TXN
GND
RSATA_RXN
RSATA_RXP
GND
SATA6G

1-4 Chapter 1: Product introduction
10. USB 2.0 connectors (10-1 pin USB3~6)
These connectors are for USB 2.0 ports. Connect the USB module
cable to any of these connectors, then install the module to a slot
opening at the back of the system chassis. These USB connectors
comply with USB 2.0 specications and support up to 480Mbps
connection speed.
Never connect a 1394 cable to the USB connectors. Doing so
will damage the motherboard!
USB+5V USB_P3- USB_P3+ GND NC
USB+5V
USB_P4-
USB_P4+
GND
USB34
PIN 1
7. System panel connector (10-1 pin PANEL)
This connector supports several chassis-mounted functions.
• System power LED (2-pin PWR_LED)
This 2-pin connector is for the system power LED. Connect the
chassis power LED cable to this connector. The system power LED
lights up when you turn on the system power, and blinks when the
system is in sleep mode.
• Hard disk drive activity LED (2-pin HDD_LED)
This 2-pin connector is for the HDD Activity LED. Connect the HDD
Activity LED cable to this connector. The HDD LED lights up or
ashes when data is read from or written to the HDD.
• ATX power button/soft-off button (2-pin PWR_BTN)
This connector is for the system power button.
• Reset button (2-pin RESET)
This 2-pin connector is for the chassis-mounted reset button for system reboot without
turning off the system power.
PIN 1
PWR BTN
PWR_LED+ PWR_LED- PWR GND
HDD_LED+
HDD_LED-
Ground
HWRST#
(NC)
F_PANEL
+PWR LED
+HDD_LED RESET
9. USB 3.1 Gen1 connector (20-1 pin USB3_12)
This connector allows you to connect a USB 3.1 Gen 1
module for additional USB 3.1 Gen 1 front or rear panel
ports. With an installed USB 3.1 Gen 1 module, you can
enjoy all the benets of USB 3.1 Gen 1 including faster
data transfer speeds of up to 5Gbps, faster charging time
for USB-chargeable devices, optimized power efciency
and backward compatibility with USB 2.0.
USB3_12
PIN 1
USB3+5V IntA_P1_SSRX- IntA_P1_SSRX+ GND IntA_P1_SSTX- IntA_P1_SSTX+ GND IntA_P1_D- IntA_P1_D+ GND
USB3+5V
IntA_P2_SSRX-
IntA_P2_SSRX+
GND
IntA_P2_SSTX-
IntA_P2_SSTX+
GND
IntA_P2_D-
IntA_P2_D+
8. Speaker connector (4-pin SPEAKER)
The 4-pin connector is for the chassis-mounted system warning speaker.
The speaker allows you hear system beeps and warnings.
+5V GND GND Speaker Out
SPEAKER
PIN 1

ASUS PRIME B350M-K 1-5
12. Serial port connector (10-1 pin COM)
This connector is for a serial (COM) port. Connect the serial port
module cable to this connector, then install the module to a slot
opening at the back of the system chassis.
PIN 1
COM
DCD
TXD
GND
RTS
RI
RXD
DTR
DSR
CTS
To erase the RTC RAM:
1. Turn OFF the computer and unplug the power cord.
2. Use a metal object such as a screwdriver to short the two pins.
3. Plug the power cord and turn ON the computer.
4. Hold down the <Del> key during the boot process and enter BIOS
setup to re-enter data.
If the steps above do not help, remove the onboard battery and short the two pins again to
clear the CMOS RTC RAM data. After clearing the CMOS, reinstall the battery.
CLRTC
+3V_BAT GND
PIN 1
11. Clear RTC RAM (2-pin CLRTC)
This header allows you to clear the Real Time Clock (RTC) RAM in CMOS. You can
clear the CMOS memory of date, and system setup parameters by erasing the CMOS
RTC RAM data. The onboard button cell battery powers the RAM data in CMOS, which
include system setup information such as system passwords.
13. Digital audio connector (4-1 pin SPDIF_OUT)
This connector is for an additional Sony/Philips Digital Interface (S/
PDIF) port. Connect the S/PDIF Out module cable to this connector,
then install the module to a slot opening at the back of the system
chassis.
SPDIF_OUT
+5V SPDIFOUT GND
14. Front panel audio connector (10-1 pin AAFP)
This connector is for a chassis-mounted front panel
audio I/O module that supports either HD Audio or
legacy AC`97 audio standard. Connect one end of the
front panel audio I/O module cable to this connector.
AAFP
AGND NC SENSE1_RETUR SENSE2_RETUR
PORT1 L
PORT1 R PORT2 R
SENSE_SEND
PORT2 L
HD-audio-compliant
pin definition
PIN 1
AGND NC NC NC
MIC2
MICPWR
Line out_R
NC
Line out_L
Legacy AC’97
compliant definition
• We recommend that you connect a high-denition front panel audio module to this
connector to avail of the motherboard’s high-denition audio capability.
• If you want to connect a high-denition front panel audio module to this connector, set
the Front Panel Type item in the BIOS setup to [HD]. If you want to connect an AC’97
front panel audio module to this connector, set the item to [AC97]. By default, this
connector is set to [HD].

1-6 Chapter 1: Product introduction
15. PCI Express 2.0 x1 slots
This motherboard has two PCI Express 2.0 x1 slots that support PCI Express x1
network cards, SCSI cards, and other cards that comply with the PCI Express
specications.
16. PCI Express 3.0/2.0 x16 slot
This motherboard supports one PCI Express 3.0/2.0 x16 graphic card that complies
with the PCI Express specications.
A B C D E F G H
PCI Express x16_1 – – – shared – – – –
PCI Express x1_1 shared – – – – – – –
PCI Express x1_2 – – – shared – – – –
M.2 – – – shared – – – –
APU USB3.0 XHCI
controller – – shared – – – – –
AMD Promonotry Chip
XHCI controller shared – – – – – – –
SATA controller – – – shared – – – –
HD audio controller – – – – – – shared –
Realtek LAN controller – – shared – – – – –
IRQ assignments for this motherboard
• For AMD AM4 A-series/Athlon™ Series processors

ASUS PRIME B350M-K 1-7
When using PCI cards on shared slots, ensure that the drivers support “Share IRQ” or that
the cards do not need IRQ assignments. Otherwise, conicts will arise between the two PCI
groups, making the system unstable and the card inoperable.
A B C D E F G H
PCI Express x16_1 – – – – – – shared –
PCI Express x1_1 shared – – – – – – –
PCI Express x1_2 – – – shared – – – –
M.2 shared – – – – – – –
APU USB3.0 XHCI
controller – – – – – – – shared
AMD Promonotry Chip
XHCI controller shared – – – – – – –
SATA controller – shared – – – – – –
HD audio controller – – – shared – – – –
Realtek LAN controller – – shared – – – – –
• For RyzenTM processors

1-8 Chapter 1: Product introduction
1.2.2 Rear panel connectors
1. PS/2 mouse (green) port. This port is for a PS/2 mouse.
2. Video Graphics Adapter (VGA) port. This 15-pin port is for a VGA monitor or other
VGA-compatible devices.
3. USB 3.1 Gen 1 ports. These four 9-pin Universal Serial Bus (USB) ports connect to
USB 3.1 Gen 1 devices.
• USB 3.1 Gen 1 devices can only be used for data storage.
• The plugged USB 3.1 Gen 1 device may run on xHCI or EHCI mode, depending on
the operating system’s setting.
• We strongly recommend that you connect USB 3.1 Gen 1 devices to USB 3.1 Gen 1
ports for faster and better performance from your USB 3.1 Gen 1 devices.
4. USB 2.0 ports. These 4-pin Universal Serial Bus (USB) ports are for USB 2.0/1.1
devices.
1 4 5
310
36 7
8
2
9
LAN port
Speed
LED
Activity Link
LED
Activity/Link LED Speed LED
Status Description Status Description
Off No link OFF 10Mbps connection
Orange Linked ORANGE 100Mbps connection
Orange (Blinking) Data activity GREEN 1Gbps connection
Orange (Blinking
then steady)
Ready to wake
up from S5 mode
LAN port LED indications
5. LAN (RJ-45) port. This port allows Gigabit connection to a Local Area Network (LAN)
through a network hub. Refer to the table below for the LAN port LED indications.

ASUS PRIME B350M-K 1-9
9. DVI-D port. This port is for any DVI-D compatible device.
DVI-D can not be converted to output from RGB Signal to CRT and is not compatible with
DVI-I.
10. PS/2 keyboard (purple) port. This port is for a PS/2 keyboard.
6. Line In port (light blue). This port connects to the tape, CD, DVD player, or other
audio sources.
7. Line Out port (lime). This port connects to a headphone or a speaker. In the 4.1, 5.1
and 7.1-channel congurations, the function of this port becomes Front Speaker Out.
8. Microphone port (pink). This port connects to a microphone.
Refer to the audio conguration table for the function of the audio ports in 2.1, 4.1, 5.1, or
7.1-channel conguration.
Audio 2.1, 4.1, 5.1, or 7.1-channel conguration
Port Headset
2.1-channel 4.1-channel 5.1-channel 7.1-channel
Light Blue (Rear panel) Line In Rear Speaker Out Rear Speaker Out Rear Speaker Out
Lime (Rear panel) Line Out Front Speaker Out Front Speaker Out Front Speaker Out
Pink (Rear panel) Mic In Mic In Bass/Center Bass/Center
Lime (Front panel) - - - Side Speaker Out

1-10 Chapter 1: Product introduction
1.3 Central Processing Unit (CPU)
The motherboard comes with an AMD AM4 socket designed for AMD
Ryzen™ / 7th Generation A-series / Athlon™ processors.
Unplug all power cables before installing the CPU.
The AM4 socket has a different pinout from the FM2+/FM2 socket. Ensure that you use a
CPU designed for the AM4 socket. The CPU ts in only one correct orientation. DO NOT
force the CPU into the socket to prevent bending the pins and damaging the CPU!
Installing the CPU
Apply the Thermal Interface Material to the CPU heatsink and CPU before you install the
heatsink and fan if necessary.
1
3
2
4

ASUS PRIME B350M-K 1-11
Installing the CPU heatsink and fan assembly
Type 2
Type 1
1
1
3
2
2
4
Remove the screws and the retention module only. Do not remove the plate on the
bottom.

1-12 Chapter 1: Product introduction
1.4 System memory
Overview
This motherboard comes with four Double Data Rate 4 (DDR4) Dual Inline Memory Module
(DIMM) sockets. The gure illustrates the location of the DDR4 DIMM sockets:
Channel Sockets
Channel A DIMM_A1
Channel B DIMM_B1
• You may install varying memory sizes in Channel A and Channel B. The system
maps the total size of the lower-sized channel for the dual-channel conguration. Any
excess memory from the higher-sized channel is then mapped for single-channel
operation.
• Always install DIMMs with the same CAS latency. For optimal compatibility, we
recommend that you install memory modules of the same version or date code (D/C)
from the same vendor. Check with the retailer to get the correct memory modules.
• For system stability, use a more efcient memory cooling system to support a full
memory load (2 DIMMs).
• Refer to www.asus.com for the latest Memory QVL (Qualied Vendors List)
Recommended memory congurations
DIMM_A1
DIMM_B1