MG-1 Mk.II | Ultimate (5090/9950X3D2)

Setup Guide

Welcome to your new MAINGEAR MG-1 Ultimate!

This guide will walk you through each step to get your system connected and powered on. Your MG-1 was professionally built, configured, and tested by the MAINGEAR team to deliver exceptional performance and reliability right out of the box. We recommend reviewing this guide in full for helpful tips and guidance on key features, including RGB lighting and Wi-Fi setup.

Before you begin

A few things to check first...

Unpack your MG-1

Before removing your system, check the inner flaps at the top of the box for helpful unboxing tips.

Tip

We strongly recommend keeping all original packaging and shipping materials. These are important if you ever need to transport your PC or send it in for upgrades or service.

Find the right spot for your MG-1

Airflow is critical for high-performance PCs and directly impacts frame rates, system stability, and component longevity. Make sure there is clear space on all sides of the system, especially near intake and exhaust areas.

⚠ Important

Avoid placing your MG-1 directly on carpet or inside enclosed cabinets and tight spaces, as this can restrict airflow and trap heat.

Let's get started

Setup

1
Connect your monitor

Connect your monitor to the graphics card on the back of your system. Supported display connections include DisplayPort and HDMI. We recommend using DisplayPort when available.

⚠ Important

Do not connect your monitor to the motherboard display ports. Your HDMI or DisplayPort cable should be plugged into the graphics card.

If your cable is going in vertically near the USB ports, it’s likely in the wrong place. The correct ports are on the graphics card, positioned horizontally near the center of the rear of the PC.

2
Connect to the internet

You can connect your system using Wi-Fi (wireless) or Ethernet (wired). A wired connection typically offers the fastest and most stable experience.

If using Wi-Fi, be sure to install the antenna first. It is included in your accessory box and attaches to the gold connectors on the rear I/O panel of your system.

Tip

Even if you’re using Ethernet, installing the antenna is recommended to enable Bluetooth functionality.

3
Connect a mouse and keyboard

Plug in your mouse and keyboard, or their wireless receivers, into any available USB port. Gaming enthusiasts are encouraged to follow our tip below.

We recommend using the rear USB ports so the front ports remain open for quick access to devices like headsets, external storage, or cameras.

Tip

Your MG-1 Ultimate features Lightning Gaming USB ports, highlighted in yellow on the rear I/O panel. These dedicated ports use dual controller interfaces to minimize input delay, delivering ultra low latency and reduced jitter for your keyboard and mouse, giving you a faster, more responsive gaming experience.

4
Connect headphones or speakers

For USB audio devices, we recommend using a blue or yellow USB 3.0 port on the rear of your system. The ports on the rear will typically provide a cleaner signal than the front panel connections.

For analog audio, connect your device using a standard 3.5mm cable to the line out audio jack on the rear I/O panel. For digital connections, an optical S/PDIF audio output is also available, located to the left of the analog line out.

Tip

For the best audio quality and lowest latency, connect audio devices directly to your MG-1 rather than through a monitor or hub when possible.

5
Connect the power cable

Securely connect the included AC power cable into the back of your MG-1, then connect it to a grounded wall outlet or a properly rated surge protector.

Locate the power supply switch on the back of the system and set it to the ON position. (I = ON, O = OFF)

⚠ Important

Not all surge protectors or uninterruptible power supplies (UPS) are created equal. If using one, make sure it is rated to handle the total power draw of all connected devices. High-performance PCs can require significant power, and using an underrated power source may lead to instability or other system issues.

6
Prepare your battlestation

Before powering on your system for the first time, it’s important to prepare your battlestation, also known as your desk.

Clear out any sandwich crumbs, empty energy drinks, loose change, and the mysterious cables from devices long forgotten. Create a space worthy of your MG-1.

It is scientifically unproven but widely accepted that a clean desk directly improves in-game performance.

7
Power on your MG-1

Press the blue power button on the top of your system to start it up. Your MG-1 will begin the boot process and automatically launch the Windows setup experience. Follow the on-screen instructions to connect to the internet, sign in or create your Microsoft account, and finish configuring your system.

Tip

Review privacy settings carefully. Windows enables several data sharing options by default. Take a minute to toggle off anything you do not need, like location tracking or diagnostic sharing.

I/O

Connectivity

Your MG-1 Ultimate offers several types of connectivity.

Rear ports

The rear ports on your MG-1 are labeled for easy identification. Supported connectivity includes the following:

  • 5G LAN (Ethernet)
  • Wi-Fi 7/Bluetooth 5.4 antenna terminals
  • 3.5mm audio (Line Out, Mic)
  • Optical audio (Toslink S/PDIF)
  • HDMI
  • USB 5Gbps Type-A
  • USB 10Gbps Type-A
  • USB 40Gbps Type-C
  • USB 2.0 Type-A
⚠ Important

While the rear I/O panel includes HDMI and DisplayPort outputs, these do not use your NVIDIA GeForce RTX 5090. For the best performance, connect your displays directly to the graphics card.

Top ports

The Front I/O on your MG-1 are located at the top of the chassis. Supported connectivity includes the following (listed top down following the image above):

  • USB 10Gbps Type-A
  • USB 20Gbps Type-C
  • 3.5mm audio combo jack
  • Reset button
  • Power button

Let it glow

RGB lighting control

Along with the case lighting, components in your MG-1 feature built in RGB illumination. You can personalize colors and effects using a free utility called Polychrome RGB, which has been pre-installed on your system. Follow the steps below to get started.

Learn more about Polychrome RGB here >

Launching Polychrome RGB

  • Polychrome RGB comes pre-installed on your MG-1.
  • You can launch it from your desktop using the ASRRGBLED shortcut.
  • If the shortcut is not visible, use the Windows search bar and type ASRRGBLED to locate the application.
Tip

If you ever need to reinstall Polychrome RGB, you can find the download link at the bottom of this page.

Controlling RGB

  • Open ASRRGBLED. If prompted to run any updates, select Yes. Do not quit the upgrade window once started.
  • In the left sidebar, locate Component Sync.
  • By default, DRAM may be selected. To control other lighting zones, deselect DRAM by clicking the blue link next to it.
  • Once DRAM is deselected, use the LED Channel section to choose specific lighting zones, or select all channels.
  • Adjust lighting modes, colors, speed, and effects as desired. Changes apply instantly.
  • To control RAM lighting separately, go to the Component tab and select DRAM.
Tip

RGB control software can occasionally behave inconsistently. You may notice brief delays or need to apply a setting more than once. If you run into any issues, our support team is happy to help.

LED Channels Guide

Default lighting channels (RGB zones) should be mapped as follows*:

  • IO COVER: Upper motherboard
  • PCB: Lower motherboard
  • ADDRESSABLE LED 1: Front intake fans + front panel + internal light bar
  • ADDRESSABLE LED 2: Upper radiator fans
  • ADDRESSABLE LED 3: Rear exhaust fan + CPU cooler (AIO pump)
  • SELECT ALL CHANNELS: Control all system lights at once

*Individual lighting zones may vary based on your configuration. RAM lights are controlled via the Component tab.

Make it yours

Standout with panel art

One of the MG-1’s award-winning design features is its swappable front panel, complete with full-bleed artwork and integrated RGB lighting, so you can personalize your system to match your style. To remove the panel, grip from the bottom and gently pull it toward you. There are no cables to disconnect. To install a new panel, simply reverse the process. Panels are fully hot swappable, so you can change them anytime, even while the system is on. When installing, align the magnets and listen for a click to ensure the panel is securely in place before letting go.

Explore the panel art gallery

Specs

For reference, your MG-1 Champion (Q1'2026) features the following configuration:

CHASSIS

MAINGEAR MG-1 Mk. II
Black

GRAPHICS CARD

NVIDIA GeForce RTX 5090
32GB GDDR7

PROCESSOR

AMD Ryzen 7 9850X3D
8 Cores - 16 Threads
Boosts to 5.6GHz

MOTHERBOARD

MSI Pro X870E-P WiFi

MEMORY

32GB RGB DDR5
6000 MT/s
(2x16GB)

STORAGE

2TB T-Force A440
Gen4 M.2 NVMe SSD

OPERATING SYSTEM

Windows 11 Home

POWER SUPPLY

MSI 1250W
80+ Gold

LIGHTING

RGB Front Panel
Internal RGB Lighting
RGB Front & Rear Fans

COOLING

MAINGEAR Epic 360
AiO Liquid Cooler
3x 120mm RGB Fans

CHASSIS FANS

3x 120mm RGB (Intake)
2x 120mm (Exhaust)
1x 120mm RGB (Exhaust)

WIRELESS CONNECTIVITY

Wi-Fi 7
Bluetooth 5.4

REAR I/O

HDMI
1x 5Gbps LAN
4x USB 2.0: 0.48Gbps (Type-A)
1x USB 4: 40Gbps (Type-C)
1x USB 3.2: 20Gbps (Type-C)
2x USB 3.2: 10Gbps (Type-A)
2x USB 3.2: 5Gbps (Type-A)
3x 3.5mm Audio Jacks

FRONT I/O

USB 10Gbps Type-A
USB 10Gbps Type-C
3.5mm Audio Combo Jack

DIMENSIONS

18.78" W
19.65" H
9.06" D

WEIGHT

Approx. 40lbs

Need a hand?

Our MAINGEAR support team is ready to assist. Have your order number handy, it's available in your order confirmation email or in your MAINGEAR account.

Phone

(+1) 908-620-9050

Mon-Fri 9am-6pm ET.

Sat 10am-1pm ET.
Sun CLOSED

Live Chat

Available for general questions and sales inquiries. Access it through the support beacon in the lower left corner. For technical support, please call or email.