Asrock B550M-ITX/ac Quick Installation Guide

Version 1.0
Published June 2020
Copyright©2020 ASRock INC. All rights reserved.

Copyright Notice:

No part of this documentation may be reproduced, transcribed, transmitted, or
translated in any language, in any form or by any means, except duplication of
documentation by the purchaser for backup purpose, without written consent of
ASRock Inc.

Products and corporate names appearing in this documentation may or may not
be registered trademarks or copyrights of their respective companies, and are used
only for identication or explanation and to the owners’ benet, without intent to

infringe.

Disclaimer:

Specications and information contained in this documentation are furnished for
informational use only and subject to change without notice, and should not be
constructed as a commitment by ASRock. ASRock assumes no responsibility for
any errors or omissions that may appear in this documentation.

With respect to the contents of this documentation, ASRock does not provide
warranty of any kind, either expressed or implied, including but not limited to
the implied warranties or conditions of merchantability or tness for a particular
purpose.

In no event shall ASRock, its directors, ocers, employees, or agents be liable for
any indirect, special, incidental, or consequential damages (including damages for
loss of prots, loss of business, loss of data, interruption of business and the like),
even if ASRock has been advised of the possibility of such damages arising from any
defect or error in the documentation or product.

is device complies with Part 15 of the FCC Rules. Operation is subject to the following
two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that

may cause undesired operation.

CALIFORNIA, USA ONLY

e Lithium battery adopted on this motherboard contains Perchlorate, a toxic substance
controlled in Perchlorate Best Management Practices (BMP) regulations passed by the
California Legislature. When you discard the Lithium battery in California, USA, please
follow the related regulations in advance.
“Perchlorate Material-special handling may apply, see www.dtsc.ca.gov/hazardouswaste/
perchlorate”

ASRock Website: http://www.asrock.com

AUSTRALIA ONLY

Our goods come with guarantees that cannot be excluded under the Australian
Consumer Law. You are entitled to a replacement or refund for a major failure and
compensation for any other reasonably foreseeable loss or damage caused by our
goods. You are also entitled to have the goods repaired or replaced if the goods fail
to be of acceptable quality and the failure does not amount to a major failure. If
you require assistance please call ASRock Tel : [phone] ext.123 (Standard
International call charges apply)

e terms HDMI® and HDMI High-Denition Multimedia Interface, and the
HDMI logo are trademarks or registered trademarks of HDMI Licensing LLC in the
United States and other countries.

CE Warning

is device complies with directive 2014/53/EU issued by the Commision of the European
Community.

is equipment complies with EU radiation exposure limits set forth for an uncontrolled
environment.
is equipment should be installed and operated with minimum distance 20cm between
the radiator & your body.

Operations in the 5.15-5.35GHz band are restricted to indoor usage only.

Radio transmit power per transceiver type

Function Frequency Maximum Output Power (EIRP)

2400-2483.5 MHz 18.5 + / -1.5 dbm

5150-5250 MHz 21.5 + / -1.5 dbm

WiFi

Bluetooth 2400-2483.5 MHz 8.5 + / -1.5 dbm

5250-5350 MHz

5470-5725 MHz

18.5 + / -1.5 dbm (no TPC)

21.5 + / -1.5 dbm (TPC)

25.5 + / -1.5 dbm (no TPC)

28.5 + / -1.5 dbm (TPC)

Motherboard Layout

10

11

13

5

3

2

1

4

DDR 4_B1 (6 4 bit, 28 8-pin m odule )

DDR 4_A1 (6 4 bit, 28 8-pin m odule )

ATXP WR1

PCIE1

HDLED RESE T

PLED PWRBT N

PANEL1

1

1

1

HD_AUDIO1

SATA3_1 _3

USB_3_ 4

1

CPU_FAN1

AMD

B550

SOCKETAM4

CLRCMOS1

RGB_LED1

1

1

ADDR_LED1

1

USB3_ 4_5

HDM I1

SATA3_2 _4

M2_ 1

DP1

CHA_FAN2/WP

CHA_FAN1
/WP

1

SPEAKER1

Top:

LINE I N

Cent er:

FRON T

Bott om:

MIC IN

M2_WIFI1

B550M-I TX/ ac

RoHS

USB 3.2 Gen1
T: USB3_3
B: USB3_TC_1

RJ- 45 LAN

USB 3.2 Gen1
T: USB1
B: USB2

USB 2. 0

T: USB1

B: USB 2

PS2

Keyb oard

/Mou se

ATX12V1

16

12

BAT1

B550M-ITX/ac

6

7

8

9

14

15

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1

No. Description

1 CPU Fan Connector (CPU_FAN1)

2 Addressable LED Header (ADDR_LED1)

3 RGB LED Header (RGB_LED1)

4 Chassis/Water Pump Fan Connector (CHA_FAN1/WP)

5 2 x 288-pin DDR4 DIMM Slots (DDR4_A1, DDR4_B1)

6 ATX Power Connector (ATXPWR1)

7 SATA3 Connectors (SATA3_1_3)

8 SATA3 Connectors (SATA3_2_4)

9 USB 3.2 Gen1 Header (USB3_4_5)

10 System Panel Header (PANEL1)

11 USB 2.0 Header (USB_3_4)

12 Clear CMOS Jumper (CLRCMOS1)

13 Chassis/Water Pump Fan Connector (CHA_FAN2/WP)

14 Chassis Speaker Header (SPEAKER1)

15 Front Panel Audio Header (HD_AUDIO1)

16 ATX 12V Power Connector (ATX12V1)

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2

I/O Panel

3

421

12 8

No. Description No. Description

1 USB 2.0 Ports (USB_12)* 7 USB 3.2 Gen1 Type-A Port (USB3_3)

2 LAN RJ-45 Port** 8 USB 3.2 Gen1 Type-C Port (USB3_TC_1)

3 Line In (Light Blue)*** 9 PS/2 Mouse/Keyboard Port

4 Front Speaker (Lime)*** 10 USB 3.2 Gen1 Type-A Port (USB3_1_2)

5 Antenna Ports 11 DisplayPort 1.4

6 Microphone (Pink)*** 12 HDMI Port

B550M-ITX/ac

56791011

* Please note that the USB_12 consume auxiliary power (+5VSB) while the other USB ports consume DUAL
Power (+5VDUAL). e USB_12 are optimal for connecting the USB Type speaker and headset..

** ere are two LEDs on each LAN port. Please refer to the table below for the LAN port LED indications.

ACT/LINK LED

SPEED LED

LAN Por t

Activity / Link LED Speed LED

Status Description Status Description

O No Link O 10Mbps connection
Blinking Data Activity Orange 100Mbps connection
On Link Green 1Gbps connection

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3

*** Function of the Audio Ports in 7.1-channel Conguration:

Port Function

Light Blue (Rear panel) Rear Speaker Out
Lime (Rear panel) Front Speaker Out
Pink (Rear panel) Central /Subwoofer Speaker Out
Lime (Front panel) Side Speaker Out

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4

B550M-ITX/ac

WiFi-802.11ac Module and ASRock WiFi 2.4/5 GHz Antennas

WiFi-802.11ac + BT Module

is motherboard comes with an exclusive WiFi 802.11 a/b/g/n/ac + BT v4.2 module
(pre-installed on the rear I/O panel) that oers support for WiFi 802.11 a/b/g/n/
ac connectivity standards and Bluetooth v4.2. WiFi + BT module is an easy-to-use
wireless local area network (WLAN) adapter to support WiFi + BT. Bluetooth v4.2
standard features Smart Ready technology that adds a whole new class of functionality
into the mobile devices. BT 4.2 also includes Low Energy Technology and ensures
extraordinary low power consumption for PCs.
* e transmission speed may vary according to the environment.

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5

WiFi Antennas Installation Guide

Step 1

Prepare the WiFi 2.4/5 GHz Antennas that come
with the package.

Step 2

Connect the two WiFi 2.4/5 GHz Antennas to
the antenna connectors. Turn the antenna clock­wise until it is securely connected.

Step 3

Set the WiFi 2.4/5 GHz Antenna as shown in the
illustration.

*You may need to adjust the direction of
the antenna for a stronger signal.

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6

Chapter 1 Introduction

ank you for purchasing ASRock B550M-ITX/ac motherboard, a reliable
motherboard produced under ASRock’s consistently stringent quality control.
It delivers excellent performance with robust design conforming to ASRock’s
commitment to quality and endurance.

Becau se the motherboard specications and the BIOS soware might be updated, the
content of this documentation will be subject to change without notice. In case any
modications of this documentation occur, the upd ated version will be available on
ASRock’s website without further notice. If you require technical support related to
this motherboard, please vi sit our website for s pecic information about the model
you are using. You may nd the l atest VGA cards and CPU suppor t list on ASRock’s
website a s well. ASRock website http://www.asrock.com.

1.1 Package Contents

ASRock B550M-ITX/ac Motherboard (Mini-ITX Form Factor)

•

ASRock B550M-ITX/ac Quick Installation Guide

•

ASRock B550M-ITX/ac Support CD

•

1 x I/O Panel Shield

•

2 x Serial ATA (SATA) Data Cables (Optional)

•

2 x ASRock WiFi 2.4/5 GHz Antennas (Opt iona l)

•

B550M-ITX/ac

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7

1.2 Specications

Platform

•

•

Mini-ITX Form Factor
Solid Capacitor design

CPU

Chipset

Memory

Supports 3

•

Processors (3000 and 4000 Series Processors)*

* Not compatible with AMD AthlonTM Processors.

Digi Power design

•

8 Power Phase design

•

AMD B550

•

Dual Channel DDR4 Memory Technology

•

2 x DDR4 DIMM Slots

•

AMD Ryzen series CPUs (Matisse) support DDR4 4600+

•

(OC)/4533(OC)/4466(OC)/4400(OC)/4333(OC)/4333(OC)/
4266(OC)/4200(OC)/4133(OC)/4000(OC)/3866(OC)/3800
(OC)/3733(OC)/3600(OC)/3466(OC)/3200/2933/2667/
2400/2133 ECC & non-ECC, un-buered memory*
AMD Ryzen series APUs (Renoir) support DDR4 4733+(OC)

•

/4666(OC)/4600(OC)/4533(OC)/4466(OC)/4400(OC)/
4333(OC)/4266(OC)/4200(OC)/4133(OC)/4000
(OC)/3866(OC)/3800(OC)/3733(OC)/3600(OC)/3466
(OC)/3200/2933/2667/2400/2133 ECC & non-ECC,

un-buered memory*
* Please refer to Memory Support List on ASRock’s website for
more information. (http://www.asrock.com/)
* Please refer to page 24 for DDR4 UDIMM maximum
frequency support.

Max. capacity of system memory: 64GB

•

Supports Extreme Memory Prole (XMP) memory modules

•

15μ Gold Contact in DIMM Slots

•

rd

Gen AMD AM4 Ryzen™ / future AMD Ryzen™

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B550M-ITX/ac

Expansion
Slot

Graphics

AMD Ryzen series CPUs (Matisse)

1 x PCI Express 4.0 x16 Slot (PCIE1: x16 mode)**

•

AMD Ryzen series APUs (Renoir)

1 x PCI Express 3.0 x16 Slot (PCIE1: x16 mode)**

•

* Supports PCIe riser cards to extend x8/x8 slots
** Supports NVMe SSD as boot disks

1 x Vertical M.2 Socket (Key E) with the bundled WiFi-

•

802.11ac module (on the rear I/O)

Integrated AMD RadeonTM Vega Series Graphics in Ryzen

•

Series APU*

* Actual support may vary by CPU

DirectX 12, Pixel Shader 5.0

•

Shared memory default 2GB. Max Shared memory supports

•

up to 16GB.
* e Max shared memory 16GB requires 32GB system memory
installed.

Dual graphics output: support HDMI and DisplayPort 1.4

•

ports by independent display controllers

Supports HDMI 2.1 with max. resolution up to 4K x 2K

•

(4096x2160) @ 60Hz

Supports DisplayPort 1.4 Input with max. resolution up to

•

5K (5120x2880)@120Hz

Supports Auto Lip Sync, Deep Color (12bpc), xvYCC and

•

HBR (High Bit Rate Audio) with HDMI 2.1 Port (Compliant

HDMI monitor is required)

Supports HDR (High Dynamic Range) with HDMI 2.1

•

Supports HDCP 2.3 with HDMI 2.1 and DisplayPort 1.4

•

Ports

Supports 4K Ultra HD (UHD) playback with HDMI 2.1 and

•

DisplayPort 1.4 Ports

Supports Microso PlayReady®

•

Audio

7.1 CH HD Audio (Realtek ALC887 Audio Codec)

•

Supports Surge Protection

•

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9

LAN

Wireless
LAN

Rear Panel
I/O

PCIE x1 Gigabit LAN 10/100/1000 Mb/s

•

Realtek RTL8111H

•

Supports Wake-On-LAN

•

Supports Lightning/ESD Protection

•

Supports Energy Ecient Ethernet 802.3az

•

Supports PXE

•

Intel® 802.11ac WiFi Module

•

Supports IEEE 802.11a/b/g/n/ac

•

Supports Dual-Band (2.4/5 GHz)

•

Supports high speed wireless connections up to 433Mbps

•

Supports Bluetooth 4.2+ High speed class II

•

2 x Antenna Ports

•

1 x PS/2 Mouse/Keyboard Port

•

1 x HDMI Port

•

1 x DisplayPort 1.4

•

2 x USB 2.0 Ports (Supports ESD Protection)

•

3 x USB 3.2 Gen1 Type-A Ports (Supports ESD Protection)

•

1 x USB 3.2 Gen1 Type-C Port (Supports ESD Protection)

•

1 x RJ-45 LAN Port with LED (ACT/LINK LED and SPEED

•

LED)
HD Audio Jacks: Line in / Front Speaker / Microphone

•

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10

Storage

Connector

4 x SATA3 6.0 Gb/s Connectors, support RAID (RAID 0,

•

RAID 1 and RAID 10), NCQ, AHCI and Hot Plug
1 x Hyper M.2 Socket (M2_1), supports M Key type 2280 M.2

•

SATA3 6.0 Gb/s module and M.2 PCI Express module up to
Gen4x4 (64 Gb/s) (with Matisse) or Gen3x4 (32 Gb/s) (with

Renoir)*
* Supports NVMe SSD as boot disks
* Supports ASRock U.2 Kit

1 x RGB LED Header

•

* Supports in total up to 12V/3A, 36W LED Strip

1 x Addressable LED Header

•

* Supports in total up to 5V/3A, 15W LED Strip

1 x CPU Fan Connector (4-pin)

•

* e CPU Fan Connector supports the CPU fan of maximum
1A (12W) fan power.

BIOS
Feature

B550M-ITX/ac

2 x Chassis/Water Pump Fan Connectors (4-pin) (Smart Fan

•

Speed Control)
* e Chassis/Water Pump Fan supports the water cooler fan of
maximum 2A (24W) fan power.
* CHA_FAN1/WP and CHA_FAN2/WP can auto detect if 3-pin
or 4-pin fan is in use.

1 x 24 pin ATX Power Connector

•

1 x 8 pin 12V Power Connector

•

1 x Front Panel Audio Connector

•

1 x USB 2.0 Header (Supports 2 USB 2.0 ports) (Supports

•

ESD Protection)

1 x USB 3.2 Gen1 Header (Supports 2 USB 3.2 Gen1 ports)

•

(Supports ESD Protection)

AMI UEFI Legal BIOS with GUI support

•

Supports “Plug and Play”

•

ACPI 5.1 compliance wake up events

•

Supports jumperfree

•

SMBIOS 2.3 support

•

CPU, CPU VDDCR_SOC, DRAM, VPPM, +1.8VSB, VDDP

•

Voltage Multi-adjustment

Temperature Sensing: CPU, Chassis/Water Pump Fans

Hardware
Monitor

OS

Certica­tions

* For detailed product information, please visit our website: http://www.asrock .com

•

Fan Tachometer: CPU, Chassis/Water Pump Fans

•

Quiet Fan (Auto adjust chassis fan speed by CPU tempera-

•

ture): CPU, Chassis/Water Pump Fans

Fan Multi-Speed Control: CPU, Chassis/Water Pump Fans

•

Voltage monitoring: +12V, +5V, +3.3V, CPU Vcore

•

Microso® Windows® 10 64-bit

•

FCC, CE

•

ErP/EuP ready (ErP/EuP ready power supply is required)

•

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11

Please realize that the re is a certain risk involved with overclocking, including
adjusting the setting in the BIOS, applying Untied Overclocking Technology, or using
third-party overclocking tool s. Overclocking may aect your system’s stability, or
even cause damage to the components and devices of your system. It should be done
at your own risk and expense. We are not responsible for possible damage caused by
overclocking.

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12

Chapter 2 Installation

is is a Mini-ITX form factor motherboard. Before you install the motherboard,
study the conguration of your chassis to ensure that the motherboard ts into it.

Pre-installation Precautions

Take note of the following precautions before you install motherboard components
or change any motherboard settings.

Make sure to unplug the power cord before installing or removing the motherboard.

•

Failure to do so may cause physical injuries to you and damages to motherboard
components.
In order to avoid damage from static electricity to the motherboard’s components,

•

NEVER place your motherboard directly on a carpet. Also remember to use a grounded
wrist strap or touch a safety grounded object before you handle the components.
Hold components by the edges and do not touch the ICs.

•

Whenever you uninstall any components, place them on a grounded anti-static pad or

•

in the bag that comes with the components.
When placing screws to secure the motherboard to the chassis, please do not over-

•

tighten the screws! Doing so may damage the motherboard.

B550M-ITX/ac

13

English

2.1 Installing the CPU

Unplug all power cables be fore installing the CPU.

1

English

14

2

B550M-ITX/ac

3

15

English

2.2 Installing the CPU Fan and Heatsink

Aer you install the CPU into this motherboard, it is necessary to install a larger
heatsink and cooling fan to dissipate heat. You also need to spray thermal grease
between the CPU and the heatsink to improve heat dissipation. Make sure that the
CPU and the heatsink are securely fastened and in good contact with each other.

Please turn o the power or remove the power cord before changing a CPU or heatsink.

Installing the CPU Box Cooler SR1

1

English

16

2

B550M-ITX/ac

3

4

1

N

FA

_

U

P

C

English

17

Installing the AM4 Box Cooler SR2

1

2

English

18

B550M-ITX/ac

3

19

English

4

1
N

FA

_

U

P

C

*e diagrams shown here are for reference only. e headers might be in a dierent position on
your motherboard.

English

20

Installing the AM4 Box Cooler SR3

1

B550M-ITX/ac

2

English

21

3

4

English

22

B550M-ITX/ac

5

FAN1

CPU_

6

1

N

FA

_
U
P

C

2

D

E

L

_

B

RG

+12V

*e diagrams shown here are for reference only. e headers might be in a dierent position
on your motherboard.

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23

2.3 Installing Memory Modules (DIMM)

is motherboard provides two 288-pin DDR4 (Double Data Rate 4) DIMM slots,
and supports Dual Channel Memory Technology.

1. For dual channel conguration , you always need to in stall identical (the same
brand, speed , size and chip-type) DDR4 DIMM pairs.

2. It is unable to activate Du al Channel Memory Technology with only one memory
module installed.

3. It is not allowed to install a DDR, DDR2 or DDR3 memory module into a DDR4
slot; otherwise, this motherboard and DIMM may be damaged.

AMD non-XMP Memory Frequency Support

Ryzen Series CPUs (Matisse):

English

UDIMM Memory Slot

A1 B1

SR - 3200

- SR 3200

DR - 3200

- DR 3200

SR SR 3200

DR DR 3200

Ryzen Series APUs (Renoir):

UDIMM Memory Slot

A1 B1

SR - 3200

- SR 3200

DR - 3200

- DR 3200

SR SR 3200

DR DR 3200

Frequency

(Mhz)

Frequency

(Mhz)

24

e DIMM only ts in one correct orientation. It will cause permanent damage to
the motherboard and the DIMM if you force the DIMM into the slot at incor rect
orientation.

1

2

B550M-ITX/ac

3

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25

2.4 Expansion Slot (PCI Express Slot)

ere is 1 PCI Express slot on the motherboard.

Before installing an ex pansion card, please make sure that the power supply is
switched o or the power cord is unplugged. Plea se read the documentation of the
expan sion card and make necessary hardware settings for the card before you start
the installation.

PCIe slots:

PCIE1 (PCIe 4.0 x16 slot) is used for PCI Express x16 lane width graphics cards.

PCIe Slot Congurations

PCIE1

Ryzen Series CPUs (Matisse) Gen4x16

Ryzen Series APUs (Renoir) Gen3x16

For a better ther mal environment, please connect a ch assis fan to the motherboard’s
chassis fan connector (CHA_ FAN1/WP or CHA _FAN2/WP) when using multiple
graphics cards.

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26