Asus Prime B840M-A

Name: Asus Prime B840M-A
Brand: Asus
SKU: 28311

Manufacturer: Asus

The Asus Prime B840M-A is a reliable Micro-ATX motherboard designed for performance and versatility. Featuring an AM5 CPU socket and support for up to 256GB of memory, it offers solid capabilities for a range of builds.

Technical features include overclocked RAM speeds of 7600 MHz, 4 memory slots, and dual BIOS support. It also provides a variety of ports, including HDMI 2.1, DisplayPort outputs, and USB Type-C, making it highly adaptable for different setups.

Pros

Supports RAID 0, RAID 1, RAID 5, and RAID 10 for flexible storage configurations and data redundancy.
Includes RGB lighting for customizable aesthetics.
Offers dual BIOS for enhanced reliability and easy recovery in case of system failure.
Has four memory slots and supports up to 256GB of memory for robust performance and upgrade options.

Cons

Does not support Wi-Fi or Bluetooth, limiting wireless connectivity options.
Lacks USB 3.2 Gen 2x2 and Thunderbolt ports, restricting high-speed data transfer and external device connectivity.
Does not support ECC memory, which may be a limitation for users needing error-correcting code for critical tasks.
No mSATA connector, limiting compatibility with older storage devices.

Who is this for?

The Asus Prime B840M-A motherboard is ideal for users who prioritize flexibility in storage and memory. With support for up to 256GB of memory and multiple RAID configurations like RAID 0, 1, 5, and 10, it suits users who need a high-capacity, reliable system for tasks such as gaming, content creation, or small-scale server use. Its dual BIOS ensures stability and safety during overclocking or system upgrades, making it an excellent choice for enthusiasts or users seeking long-term reliability.

Who is this NOT for?

This motherboard is not ideal for users who require advanced wireless connectivity, as it lacks both Wi-Fi and Bluetooth support. Additionally, those looking for high-speed data transfer options may be disappointed by the absence of USB 3.2 Gen 2x2 and Thunderbolt ports. The lack of support for ECC memory also makes it less suitable for critical workloads or environments where data integrity is a priority.

General info:

CPU socket	AM5
form factor	Micro-ATX
release date	January 2025
supports Wi-Fi	✕
Has Bluetooth	✕
HDMI version	HDMI 2.1
Easy to overclock	✓
has RGB lighting	✓
Easy to reset BIOS	✓
Has dual BIOS	✓
CPU sockets	1
Has integrated graphics	✕
warranty period	3 years
height	244 mm
width	244 mm
Has integrated CPU	✕

The Asus Prime B840M-A motherboard features an AM5 CPU socket and a compact Micro-ATX form factor, making it suitable for a variety of PC builds. It includes HDMI 2.1 support for high-definition video output, RGB lighting for customizable aesthetics, and dual BIOS for added reliability. The motherboard also offers an easy-to-overclock design and a simple CMOS reset for smooth troubleshooting. Additionally, it has a 3-year warranty period, but does not support Wi-Fi, Bluetooth, or integrated graphics.

Memory:

maximum memory amount	256GB
overclocked RAM speed	7600 MHz
memory slots	4
DDR memory version	5
memory channels	2
Supports ECC memory	✕

The Asus Prime B840M-A motherboard supports up to 256GB of maximum memory and features four memory slots for expansion. It is compatible with DDR5 memory and offers overclocked RAM speeds of up to 7600 MHz. The motherboard supports dual memory channels but does not support ECC memory, making it suitable for high-performance applications where error correction is not required.

Ports:

USB 3.2 Gen 2 ports (USB-A)	2
USB 3.2 Gen 1 ports (USB-A)	1
USB 3.2 Gen 2 ports (USB-C)	0
USB 3.2 Gen 1 ports (USB-C)	0
USB 2.0 ports	4
USB 3.2 Gen 2x2 ports	0
USB 4 40Gbps ports	0
USB 4 20Gbps ports	0
Thunderbolt 4 ports	0
Thunderbolt 3 ports	0
has an HDMI output	✓
DisplayPort outputs	2
RJ45 ports	1
Has USB Type-C	✓
eSATA ports	0
DVI outputs	0
has a VGA connector	✕
PS/2 ports	0

The Asus Prime B840M-A motherboard provides a solid selection of ports, including two USB 3.2 Gen 2 ports (USB-A), one USB 3.2 Gen 1 port (USB-A), and four USB 2.0 ports for a range of peripherals. It also features an HDMI output and two DisplayPort outputs for video connectivity. Additionally, the board offers one RJ45 Ethernet port and a USB Type-C port for modern device compatibility, though it does not support Thunderbolt or VGA outputs.

Connectors:

USB 3.2 Gen 1 ports (through expansion)	2
USB 2.0 ports (through expansion)	4
SATA 3 connectors	4
fan headers	4
USB 3.0 ports (through expansion)	2
M.2 sockets	3
Has TPM connector	✓
U.2 sockets	0
Has mSATA connector	✕
SATA 2 connectors	0

The Asus Prime B840M-A motherboard offers a variety of expansion options with three M.2 sockets, four SATA 3 connectors, and four fan headers for cooling. It includes two USB 3.2 Gen 1 connectors and additional ports for USB 2.0 and USB 3.0 devices through expansion. The motherboard also features a TPM connector for added security, but lacks mSATA and U.2 sockets.

Expansion slots:

PCIe 4.0 x16 slots	1
PCIe 5.0 x16 slots	0
PCIe 3.0 x16 slots	2
PCIe x1 slots	0
PCI slots	0
PCIe 2.0 x16 slots	0
PCIe x4 slots	0
PCIe x8 slots	0

The Asus Prime B840M-A motherboard provides a range of PCIe slots for expansion, including one PCIe 4.0 x16 slot and two PCIe 3.0 x16 slots, allowing for flexible graphics and other card configurations. However, it does not include PCIe x1, x4, x8, or PCI slots, nor does it support PCIe 5.0 or PCIe 2.0 x16 slots.

Audio:

audio channels	7.1
Has S/PDIF Out port	✕
audio connectors	3

The Asus Prime B840M-A motherboard supports 7.1 audio channels for high-quality sound output. It includes three audio connectors for easy connection to speakers or headphones, but does not offer an S/PDIF Out port for digital audio output.

Storage:

Supports RAID 1	✓
Supports RAID 10 (1+0)	✓
Supports RAID 5	✓
Supports RAID 0	✓
Supports RAID 0+1	✕

The Asus Prime B840M-A motherboard supports multiple RAID configurations, including RAID 0, RAID 1, RAID 5, and RAID 10 (1+0), allowing for flexible storage options and enhanced data protection. However, it does not support the RAID 0+1 configuration.

Final Verdict

The Asus Prime B840M-A motherboard is a solid choice for users seeking reliability and expandability, particularly for those who need high memory capacity and RAID support. Its dual BIOS, easy overclocking, and support for up to 256GB of memory make it a good option for enthusiasts and those building a robust system. However, it may not be ideal for users who require built-in wireless connectivity or advanced data transfer options like Thunderbolt. Overall, this motherboard is best suited for those focused on stability and expandability in a more traditional desktop build.