Intel LGA-1151 mATX motherboard with LED lighting, DDR4 2666MHz, M.2 support, SATA 6Gbps
  • ASUS OptiMem: Careful routing of traces and vias to preserve signal integrity for improved memory stability.
  • Fan Xpert: Flexible controls for ultimate cooling and quietness, plus GPU-temperature sensing for cooler gaming.
  • 5X Protection III: Multiple hardware safeguards for all-round protection.
  • Ultrafast connectivity: Native M.2 support for Lightning-fast storage speeds
PRIME B365M-K/CSM

1 PS/2 KB & MS

2 D-Sub port

3 DVI-D port

4 4 x USB 3.1 Gen 1 ports

5 LAN

6 2 x USB 2.0 ports

7 Audio

8
PCI Express 3.0
  • ASUS SafeSlot Core support
9
Audio Features
  • LED-Illuminated Design
  • Audio Shielding
  • Premium Japanese Audio Capacitors
  • Dedicated Audio PCB Layers

10 DIGI+VRM & EPU

11 DDR4 2666/2400/2133 support

12 Support 9th/ 8th Gen
Intel® Core™
Pentium® Gold and
Celeron® processors
Intel® LGA 1151 Socket

13 32Gb/s M.2 support SATA &
x4 PCIE mode Intel® Optane™
Memory Ready

14 Intel® B365 Chipset

15 6 x SATA 6Gb/s

16 2 x Front USB 3.1 Gen 1

Prime

ASUS Prime 300 Series motherboards provide the solid foundation needed for your first build, plus flexibility to grow with your ambitions. We've melded all the good stuff that's packed into the latest processors with essential ASUS design and engineering, so you benefit from industry-leading technologies — including automated system tuning, comprehensive cooling controls, and immersive onboard audio. When you build with an ASUS Prime 300 Series motherboard, you build smart, easy and affordably.

ASUS Corporate Stable Model

ASUS Corporate Stable Model (CSM) is a commercial program designed to provide stable and reliable motherboards. Offering up to 36-month product lifecycle support and 6-month end-of-life notice to allow sufficient lead times for your organization to get ready for product transitions. Each purchase of an ASUS CSM motherboard comes with ASUS Control Center Express - server-grade IT management software.

Learn more about ASUS Corporate Stable Model >

* Lifecycle support for consumer chipsets (eg. Q370, H370, B360,H270,B250) is set at 15 months. Program offerings may vary by region. Please consult your local sales representative for more information.

ASUS Control Center Express

ASUS Control Center Express is centralized IT management software designed to provide a convenient, effective, secure and cost-saving solution for enterprises, small and medium-sized businesses, and data centers in any type of industry. With the help of ASUS Control Center Express, your organization will be equipped to achieve success in even the most challenging modern IT environments.

Learn more about ASUS Control Center Express>
Optimize IT endpoint management

Designed to assist IT staff in monitoring and controlling devices within their corporate networks, and facilitate inventory checking in multiple locations remotely

Automate IT maintenance

Allows IT staff to schedule automatic updates of the latest BIOS, software and utilities to specific or all devices at off-peak times, enhancing system stability and IT operational flexibility

Securely manage all of endpoints

Securely manage endpoint configuration, portable storage access and PC software applications by enabling them to create grouping rules on individual devices

Tune it your way

Improved DDR4 stability

ASUS OptiMem preserves memory signal integrity by routing traces and vias to the optimal PCB layer, and our T-Topology trace layout ensures time-aligned signaling by balancing trace lengths between memory slots. These enhancements allow the Prime 300 Series to support a wide range of dual and quad-DIMM memory kits, while providing your rig with the stability it needs to deal with any type of workload - whether you're gaming or running intensive applications

A larger signal eye results in improved stability, more overclocking headroom, and lower operating voltages

ASUS OptiMem advantage:
ASUS OptiMem
53.12 V*pS
Reference design
72.51 V*pS
26%
Reduction in crosstalk
ASUS OptiMem benefits:
  • Improved memory stability and compatibility
  • Allows lower memory latencies at equivalent voltages
  • Improved memory frequency margin

Tested by using Synopsys HSPICE simulation software

All-round energy efficiency

With the Energy Processing Unit (EPU) you'll enjoy system-wide power savings. The EPU automatically optimizes power consumption and maximizes savings with Away mode — a smart setting that creates an extreme energy-saving scenario by shutting down unused I/O controllers.

Flexible cooling controls

Prime 300 Series motherboards offer comprehensive control over system fans, via the included Fan Expert software. Auto-Tuning mode intelligently configures all parameters with a single click.

Cooler by design

Prime 300 Series features the most comprehensive cooling controls ever, configurable via ASUS Fan Xpert software or the UEFI BIOS.

Each header can monitor and react to dedicated thermal sensors.

Each onboard CHA FAN header supports PWM and DC mode.



* Specifications and features vary by model, and all images are illustrative. Please refer specification pages for full details.

Media-acclaimed UEFI BIOS

The UEFI BIOS is an early waypoint on any PC-building journey, and Prime 300 Series has one of the best in the business.

Q-Fan Control Can configure the fan's operating speed manually, or use the easy pre-configured fan profiles to select Standard, Silent, Turbo or Full Speed modes, plus automatic switch to full speed if the temperature hits 75°C.

Learn more
EZ mode

Intuitive graphical fan control Fine-tune individual fans simply by dragging a curve with the mouse.

SATA Information: Display SATA port details that help you easily recognize drives.

Fast Clock Adjustment: Use mouse controls to change the time and date.

Advanced mode

My Favorites Quickly find tuning options and add preferred tools to the list.

User Profile Save BIOS settings for migration to new BIOS version or system.

SATA Port Renaming: Rename SATA ports for easy identification.

Ultrafast connectivity

USB 3.1 Gen 1 front-panel connector

Future-proof connectivity

USB 3.1 Gen 1 is right where you need it, with two super-speed headers for the front panel. Experience data-transfer speeds up to 10X faster than USB 2.0 with instant plug-and-play connectivity, and avoid back-breaking contortions in the hunt for hard-to-reach rear ports.

* Specifications and features vary by model, and all images are illustrative. Please refer specification pages for full details.

M.2

Speed up with onboard M.2

With x4 PCI Express® 3.0/2.0 bandwidth, M.2 supports up to 32Gbps data-transfer speeds. It's the perfect choice for an operating system or application drive, providing fast access to data.

* Specifications and features vary by model, and all images are illustrative. Please refer specification pages for full details.

Intel Optane memory

Intel Optane memory ready

Intel Optane™ is a revolutionary non-volatile memory technology supported by Prime 300 Series motherboards. Intel Optane memory modules accelerate attached storage to reduce boot and load times, so everything feels faster and more responsive.

LANGuard

Pumped-up throughput, 2.5x higher surge tolerance

ASUS LANGuard is hardware-level networking protection that employs signal-coupling technology and premium anti-EMI surface-mounted capacitors to ensure a more reliable connection and better throughput.

Turbo LAN

Network-optimization software for customizable packet prioritization

Turbo LAN with cFosSpeed traffic-shaping technology allows you to configure application priority via an intuitive interface, and reduces network lag.

Reliable stability and compatibility

Built to Last

ASUS is the world's leading motherboard brand. Our motherboards are extensively tested for compatibility with more than 1,000 components and devices, and each new model undergoes a minimum of 8,000 hours of strict validation — offering the peace of mind of knowing that your ASUS motherboard is fit for all environments and applications. Choosing ASUS is an assurance of trouble-free DIY experiences.

5X

Protection III

Hardware safeguards to ensure long-term durability.

520+

DDR4 compatibility

Industry-leading DDR4 memory compatibility for best flexibility and reassurance.

1000+

compatible devices

Compatibility with a range of CPUs, memory modules, graphics cards and more.

8000+

validation hours

Extensive testing with latest components for enhanced reliability, compatibility and safety.

Prime 300 Series motherboards are engineered with industry-leading 5X Protection III, employing the finest components, excellent circuit design and exacting standards to guarantee the quality and long-term durability of your investment. That means exceptional protection and stability for your build — thanks to decades of engineering experience from the world's leading motherboard brand.

Learn more

SafeSlot Core

Fortified PCIe slot prevents damage

SafeSlot Core is the ASUS-exclusive PCIe® slot. Featuring a fortified design that's anchored to the motherboard by a special hook, Safeslot Core provides 1.6X-stronger retention and 1.3X-greater shearing resistance than standard expansion slots.

Our Prime 300 Series motherboards also have strengthened solder points around both the PCIe and DIMM pins.

LANGuard

Pumped-up throughput, 2.5X-higher surge tolerance

ASUS LANGuard is hardware-level networking protection that employs signal-coupling technology and premium anti-EMI surface-mounted capacitors to ensure a more reliable connection and better throughput.

Overvoltage Protection

World-class circuit-protecting power design

An exclusive circuit design with built-in voltage regulators protects your motherboard from damage caused by unexpected high-level voltages from unstable or inferior power supplies.

DIGI+ VRM

Precision control for stable power

ASUS-exclusive DIGI+ VRM intelligently delivers power to the processor based on real-time demands, reducing energy waste and improving system stability.

DRAM Overcurrent Protection

Short-circuit damage prevention

Onboard resettable fuses prevent overcurrent and short-circuit damage. This extends beyond I/O ports to DRAM ― so it provides a safeguard to protect the lifespan of your system and connected devices.

Stainless-steel back I/O panel

3X corrosion-resistance for greater durability

Corrosion-resistant stainless-steel back I/O panels bonded with chromium oxide assure a lifespan that's 3X longer than ordinary panels.

ESD Guards

Electrostatic discharge protection

ASUS ESD Guards prolong the life of components while preventing damage from electrostatic discharge, providing protection for up to +/- 10kV of air discharge and +/- 6kV of contact discharge.

1000+

Compatible devices and components

The superior compatibility of Prime 300 Series is evidenced by our extensive list of supported devices — which includes thousands of compatible components — and our Qualified Vendor List (QVL) that identifies memory compatibility. It all adds up to more choices for worry-free PC-building experiences.

8000+

VALIDATION HOURS

ASUS motherboards offer superb endurance. We verify this by subjecting every board to more than 8,000 hours of stringent tests. A barrage of burn-in, environmental, compatibility, software and safety tests confirm that our motherboards are exceptionally robust. It also shows that ASUS reliability surpasses industry standards, ensuring that every component is designed to function flawlessly in any environment.

Learn more
Temperature and humidity tests
Ensures components withstand extreme conditions.
Thermal measurement tests
Ensures that the system remains cool and stable under the heaviest loads.
Insertion tests
Every port and connector is put through repeated installation cycles.
Aging tests
Up to 48-hour aging test ensures reliability.
Power-consumption tests
Delivers world-class energy efficiency.
Temperature and DC margin tests
Ensures that the motherboard is capable of coping with voltages fluctuations caused by varying temperatures.
Thermal-shock tests
Ensures ability to survive temperature changes during transportation.
Non-operation shock tests
Built to withstand jolts that may occur during shipping.
Burn-in tests
Every component is checked to ensure flawless operation.
Installation tests
Connector placement is double-checked to ensure hassle-free installation.
Drop tests
Drop tests from various heights ensure durability.
Salt and spray tests
Tested for I/O reliability, prolonged lifespan and rust-resistance.
Upgrade to unrivalled audio

Outstanding audio

Combined onboard features deliver elevated audio

Intelligent design and premium hardware create audio quality unlike anything you've ever experienced!

Audio shielding

Separates analog/digital signal domains, significantly reducing multi-lateral interference.

Separate layer for left and right tracks

Ensures minimal crosstalk between audio paths.

Premium Japanese audio capacitors

Premium parts provide an immersive sound signature, with exceptional fidelity.

* Specifications and features vary by model, and all images are illustrative. Please refer specification pages for full details.

Brighten Up Your Build

LED-illuminated control for trace paths

Built-in LED lighting options illuminate your build in a variety of eye-catching styles.

* Specifications and features vary by model, and all images are illustrative. Please refer specification pages for full details.

Intel B365 chipset The Intel® B365 is a single-chipset design that supports Socket 1151 for 9th Gen and 8th Gen Intel® Core™, Pentium® Gold and Celeron® processors. It provides improved performance by utilizing serial point-to-point links, allowing increased bandwidth and stability. Additionally, the B365 chipset provides a maximum of eight USB 3.1 Gen 1 ports, six SATA 6Gbps ports, and 32Gbps M.2 and PCIe 3.0 lane-speed support, for faster data retrieval. Intel B365 also supports integrated-graphics, so you'll enjoy the very latest in graphics performance.

Ready for Socket 1151 for 9th / 8th Gen Intel® Core™, Pentium® Gold and Celeron® processors This motherboard supports Socket 1151 for 9th Gen and 8th Gen Intel® Core™, Pentium® Gold and Celeron® processors, with integrated graphics, memory and PCI Express controllers to support onboard graphics output with dedicated chipsets, dual-channel (4-DIMM) DDR4 memory and 16 PCI Express 3.0/2.0 lanes for great performance.

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