MAG FORGE 321R AIRFLOW - Desktop Computer MSI - Free user manual and instructions

Product Type	Desktop Computer Case
Brand	MSI
Model	MAG FORGE 321R AIRFLOW
Form Factor	Mid Tower
Motherboard Support	ATX, Micro-ATX, Mini-ITX
Dimensions (H x W x D)	485 mm x 220 mm x 460 mm
Weight	7.5 kg
Material	Steel, Tempered Glass, ABS
Side Panel	Tempered Glass
Cooling System (Included Fans)	2 x 120mm Front, 1 x 120mm Rear
Front I/O Ports	USB 3.2 Gen 1 Type-C, USB 3.2 Gen 1 Type-A, Audio Jacks
Expansion Slots	7
Drive Bays	2 x 3.5", 2 x 2.5"
Max GPU Length	340 mm
Max CPU Cooler Height	165 mm
PSU Support	Bottom mount, ATX
Dust Filters	Front, Top, Bottom
Color	Black
Warranty	2 years

Frequently Asked Questions - MAG FORGE 321R AIRFLOW MSI

What motherboard form factors are compatible with the MSI MAG FORGE 321R AIRFLOW?

The case supports ATX, Micro-ATX, and Mini-ITX motherboards. Ensure you align the standoffs correctly for your board size.

How do I clean the dust filters?

Remove the front, top, and bottom dust filters by gently pulling them out. Wash with warm soapy water, let dry completely, then reinstall.

What is the maximum GPU length that fits in this case?

The maximum GPU length is 340 mm. Remove any drive cages or fan mounts if needed for longer cards.

Does the case come with pre-installed fans?

Yes, it includes three 120 mm fans: two in the front (intake) and one in the rear (exhaust). Additional fans can be installed on top.

How many storage drives can I install?

You can install up to 2 x 3.5" HDDs and 2 x 2.5" SSDs. The 2.5" mounts are located behind the motherboard tray.

Can I install a liquid cooling radiator?

Yes, the front supports up to 360 mm radiators, the top up to 240 mm, and the rear up to 120 mm. Check clearance with your components.

What power supply form factor is supported?

The case supports standard ATX power supplies. It is mounted at the bottom with a dust filter. Ensure the fan faces downward or upward as needed.

How do I remove the tempered glass side panel?

Unscrew the two thumbscrews at the rear of the side panel. Gently pull the panel outward and lift it off. Handle with care to avoid breakage.

What are the front I/O ports?

The front panel includes one USB 3.2 Gen 1 Type-C, one USB 3.2 Gen 1 Type-A, and audio jacks for headphone and microphone.

Is the MSI MAG FORGE 321R AIRFLOW suitable for a gaming build?

Absolutely. Its mesh front panel and included fans provide excellent airflow, and it supports high-end GPUs and liquid cooling for powerful gaming systems.

USER MANUAL MAG FORGE 321R AIRFLOW MSI

MAG Series

PC Case

MAG FORGE 320R AIRFLOW

MAG FORGE 321R AIRFLOW

MAG FORGE 120A AIRFLOW

MAG FORGE 121A AIRFLOW

User Guide

Contents

Specifications....3

Accessories 5

Case Features (320R/ 321R) ....6

Case Features (120A) 7

Case Features (121A) 8

Side and Front View....9

I/O and Buttons (320R)....10

I/O and Buttons (321R)....11

I/O and Buttons (120A / 121A)....12

Side Panel Removal....13

Front Bezel Removal....14

Motherboard Installation ....15

Graphics Card Installation....16

SSD & HDD Installation (320R/ 321R) ....17

SSD & HDD Installation (120A / 121A) ....18

PSU Installation....19

Top Panel I/O Connection ....20

Control Board Connection (320R) 21

Control Board Connection (321R) 23

Control Board Connection (120A / 121A) 25

General Information 26

Specifications

Comparison of Key Differences

Product Name	MAG FORGE320R/ 321RAIRFLOW	MAG FORGE 120AAIRFLOW	MAG FORGE 121AAIRFLOW
Dimensions (DxWxH)	472.5 x 210 x 498mm	411.6 x 210 x 498mm	411.6 x 210 x 498mm
Top Radiator Support	120 / 140 / 240 /280 / 360 mm	120 / 240 mm 120 /	240 mm
Pre-installed Fan	Top: NoFront: 3 x 120mmARGB fansRear: 1 x 120mmARGB fan	Top: 2 x 120mmAuto-RGB fansFront: 3 x 120mmAuto-RGB fansRear: 1 x 120mmAuto-RGB fan	Front: 3 x 120mmAuto-RGB fansRear: 1 x 120mmAuto-RGB fan
Side Fans Support 2 x 120mm No No
Maximum GPU Length	390mm(Pre-installedfront fan)	330mm(Pre-installedfront fan)	330mm(Pre-installedfront fan)
Drive Bays	1 x 2.5” SSD2 x Combo3.5” /2.5”	3 x 2.5” SSD2 x 3.5” HDD	3 x 2.5” SSD2 x 3.5” HDD
LED Controller	LED controllerwith Mystic LightSync	LED controller(Standalone)	LED controller(Standalone)

Basic Information

Case Type Mid Tower
Supported Motherboard Sizes ATX, Micro-ATX, Mini-ITX

Cooling Fan Support

Top 3 x 120mm or 2 x 140mm
Front 3 x 120mm or 2 x 140mm
Rear 1 x 120mm
PSU Shroud 2 x 120mm

Expansion Slots

PCIe Slots 7 slots

I/O Ports and Buttons

USB Ports	2 x USB 3.2 Gen1 Type-A1 x USB 3.2 Gen2 Type-C (321R)
Audio Ports	1 x Audio jack (120A / 121A / 320R)1 x Micphone jack (120A / 121A / 320R)1 x Audio/Micphone Combo Jack (321R)
Buttons	1 x Reset button (120A / 121A)1 x Power button1 x LED switch button (120A / 121A / 320R)

Chassis Clearances

Maximum CPU Cooler Height 160mm
Front Radiator Support 120 / 140 / 240 mm
PSU Support	160mm (with 3.5” HDD tray)200mm (without 3.5” HDD tray)

Materials

Metal Specification SPCC 0.5
Front Bezel Material Mesh + Plastic
Left Side Panel 4mm tempered glass
Dust Filter	Top: Magnetic filterSide: Magnetic filterBottom: Plastic filter

Accessories

Item Name / Q'ty Used for

	Cable ties x5	Cable management
	Screw #6-32 10mm x2	Securing drive tray
	Stand-off #6-32 6.5mm x4	Motherboard Stud
	Screw M3 5mm x20	Motherboard / SSD
	Screw #6-32 6mm x6	Securing PSU / PCIe Card
	Screw #6-32 5mm x4	3.5” HDD
	PCIe slot cover x2	PCIe slot protection
	1 to 4 fan splitter cable x1 (For 320R only)	Connecting 4 fans

Case Features (320R/ 321R)

Case Features (120A)

Case Features (121A)

Side and Front View

320R/ 321R

120A / 121A

I/O and Buttons (320R)

Item Description

1 USB 3.2 Gen 1 5Gbps Type-A port

2 Microphone jack

3 Audio jack

4 LED switch button

5 Power button

I/O and Buttons (321R)

Item Description

1 USB 3.2 Gen 2 10Gbps Type-C port

2 USB 3.2 Gen 1 5Gbps Type-A port

3 Audio/Micphone Combo Jack

4 LED switch button

5 Power button

I/O and Buttons (120A / 121A)

Item Description

1 LED switch button

2 USB 3.2 Gen 1 5Gbps Type-A port

3 Microphone jack

4 Audio jack

5 Reset button

6 Power button

Side Panel Removal

Front Bezel Removal

Motherboard Installation

Graphics Card Installation

SSD & HDD Installation (320R/ 321R)

SSD & HDD Installation (120A / 121A)

PSU Installation

Top Panel I/O Connection

Control Board Connection (320R)

Addressable RGB LED Strip Connection

Addressable RGB LED Fan Connection

• Please always turn off the power supply and unplug the power cord from the power outlet before installing or removing the ARGB LED Strip.
• Please ensure all cables are securely connected before powering on.
• This LED Hub can support up to 10 MSI devices or 6 non-MSI devices. • Each port can support a maximum of 64 ARGB LEDs, with a total of no more than 128 LEDs.
• Exceeding these limits may cause ARGB LEDs to display abnormal colors, flicker, or be unable to change colors.

LED Switch Button Function (320R)

• Single press to toggle between LED effects.
• Long press for three seconds to sync with the motherboard.

LED Effect Sequence (320R)

After pressing the LED Switch button, the LED effect sequence is as follows:

1 Solid red

2 Solid green

3 Solid blue

4 Solid purple

5 Solid cyan

6 Solid yellow

7 Solid white

8 Rainbow color cycling

9 Color running effect

10 Gradient color transition effect

11 Rainbow color breathing

12 Color breathing

13 Rainbow flashing

14 Color flashing

Control Board Connection (321R)

Addressable RGB LED Strip Connection

Addressable RGB LED Fan Connection

• Please always turn off the power supply and unplug the power cord from the power outlet before installing or removing the ARGB LED Strip.
• Please ensure all cables are securely connected before powering on.
• This LED Hub can support up to 10 MSI devices or 6 non-MSI devices. • Each port can support a maximum of 64 ARGB LEDs, with a total of no more than 128 LEDs.
• Exceeding these limits may cause ARGB LEDs to display abnormal colors, flicker, or be unable to change colors.

LED Switch Button Function (321R)

• Single press to toggle between LED effects.
• Long press for three seconds to sync with the motherboard.

LED Effect Sequence (321R)

After pressing the LED Switch button, the LED effect sequence is as follows:

1 Solid red

2 Solid green

3 Solid blue

4 Solid purple

5 Solid cyan

6 Solid yellow

7 Solid white

8 Rainbow running

9 Single-Color running

10 Gradient running

11 Rainbow color breathing

12 Single-Color breathing

13 Rainbow flashing

14 Single-Color flashing

Control Board Connection (120A / 121A)

IMPORTANT

• The control board’s fan header is a special specification and is not compatible with standard ARGB and RGB fans.
• Please always turn off the power supply and unplug the power cord from the power outlet before installing or removing the Auto-RGB fan.
• Please ensure all cables are securely connected before powering on.

LED Switch Button Function (120A / 121A)

• Single press for RGB rainbow effect.
• Press again to turn off LED lighting.

General Information

Copyright and Trademarks Notice

Copyright © Micro-Star Int'l Co., Ltd. All rights reserved.

The MSI logo used is a registered trademark of Micro-Star Int’l Co., Ltd. All other marks and names mentioned may be trademarks of their respective owners. No warranty as to accuracy or completeness is expressed or implied. MSI reserves the right to make changes to this document without prior notice.

All text, images, illustrations, and other content in this manual are the property of MSI. No part of this manual may be reproduced, distributed, or used in any form without the written permission of MSI.

Revision History

• Version 1.0, 2023/08, First release. • Version 1.1, 2024/05, Modifying the note for the ARGB LED Hub. • Version 1.2, 2024/10, Add 121A. • Version 1.3, 2024/12, Add 321R.