ASUS PRIME B850M-K-CSM is the CSM (Corporate Stable Model) edition of the PRIME B850M-K, aimed at business deployments. This micro-ATX AM5 board uses the AMD B850 chipset with two DDR5 slots up to 128GB, two M.2 slots, four SATA 6Gb/s ports, Realtek 2.5Gb Ethernet and a rear PS/2 combo port.
Product released: January 1, 2025
Latest firmware version
Version 1804, released September 21, 2026
Last checked for updates: Oct 31, 2026 06:06 UTC
What's new in version 1804
1. Update to AGESA ComboAM5 PI 1.3.0.1d.
2. Enhanced memory performance, system stability, and compatibility with CXMT memory chips for improved low-latency operation.
Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
LatestUpdate has tracked 15 versions of ASUS PRIME B850M-K-CSM firmware, released between March 11, 2025 and September 21, 2026.
Version 1804 - September 21, 2026: 1. Update to AGESA ComboAM5 PI 1.3.0.1d. 2. Enhanced memory performance, system stability, and compatibility with CXMT memory chips for improved low-latency op…
Version 1686 - July 2, 2026: Updated AGESA ComboAM5 PI 1.3.0.1b Patch A to support the GNR Transparent Secure Memory Encryption (TSME) feature. Before running the USB BIOS Flashback tool,…
Version 1681 - June 22, 2026: 1.Update AGESA ComboAM5 PI 1.3.0.1b. 2.Add support for EXPO ULL memory profiles. 3.Optimize ECC-UDIMM memory performance. Before running the USB BIOS Flashback…
Version 1670 - April 29, 2026: New memory profile support. Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
Version 1654 - April 27, 2026: "• Update AGESA ComboAM5 PI 1.3.0.1. Note: This BIOS version cannot be rolled back to previous versions. Before running the USB BIOS Flashback tool, please ren…
Version 1644 - March 23, 2026: "1. AGESA updated to ComboAM5 PI 1.3.0.0a. 2. Provide additional stability margin during high-frequency DDR5 training. 3. Addresses potential boot failures and…
Version 1642 - February 26, 2026: 1. AGESA updated to ComboAM5 PI 1.3.0.0a. 2. Provide additional stability margin during high-frequency DDR5 training. 3. Addresses potential boot failures and…
Version 1627 - February 11, 2026: "1. AGESA updated to ComboAM5 PI_Pre1.3.0.0 for better security. 2. Enhanced system performance and stability. 3. Improved memory compatibility for JEDEC-compl…
Version 1402 - November 24, 2025: "1.AGESA updated to ComboAM5 PI 1.2.7.0. 2.Improves compatibility with various CPUs and devices. Note: This BIOS version cannot be rolled back to previous vers…
Version 1087 - October 22, 2025: Updated AGESA to ComboAM5 PI 1.2.0.3g. Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
Version 1081 - September 19, 2025: Improve system stability. Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
Version 1078 - August 1, 2025: 1. Updated AGESA to ComboAM5 PI 1.2.0.3f. 2. Enhanced system performance, stability, device compatibility, and overclocking support. Before running the USB BIO…
Version 1063 - June 27, 2025: 1. Updated AGESA to ComboAM5 PI 1.2.0.3e for upcoming CPU compatibility. 2. Enhanced system performance and stability. 3. Important: This update is irreversibl…
Version 1028 - April 30, 2025: This update enhances compatibility with high-capacity memory modules and improves overall system performance. Before running the USB BIOS Flashback tool, pleas…
Version 0403 - March 11, 2025: First Release Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
Update prediction
A firmware update is expected soon, between October 12, 2026 and November 17, 2026.
ASUS typically releases firmware updates for this product approximately every 47 days.
ASUS PRIME B850M-K-CSM is the CSM (Corporate Stable Model) edition of the PRIME B850M-K, aimed at business deployments. This micro-ATX AM5 board uses the AMD B850 chipset with two DDR5 slots up to 128GB, two M.2 slots, four SATA 6Gb/s ports, Realtek 2.5Gb Ethernet and a rear PS/2 combo port. It was originally released on January 1, 2025.
What is the latest firmware version of ASUS PRIME B850M-K-CSM?
The latest firmware version of ASUS PRIME B850M-K-CSM is 1804. It was released on September 21, 2026.
What changed in ASUS PRIME B850M-K-CSM firmware version 1804?
ASUS PRIME B850M-K-CSM firmware version 1804 includes the following changes: 1. Update to AGESA ComboAM5 PI 1.3.0.1d.
2. Enhanced memory performance, system stability, and compatibility with CXMT memory chips for improved low-latency operation.
Before running the USB BIOS Flashback tool, please rename the BIOS file (A5687.CAP) using BIOSRenamer.
Where can I download the latest ASUS PRIME B850M-K-CSM firmware?
Details and download instructions for the latest ASUS PRIME B850M-K-CSM firmware (version 1804) are on ASUS's official release page: https://www.asus.com/motherboards-components/motherboards/csm/prime-b850m-k-csm/helpdesk_bios/
How often does ASUS release firmware updates for ASUS PRIME B850M-K-CSM?
We have tracked 15 firmware versions of ASUS PRIME B850M-K-CSM. Based on historical patterns, updates are released approximately every 47 days.
When is the next ASUS PRIME B850M-K-CSM firmware update expected?
Based on this product's update history, a firmware update for ASUS PRIME B850M-K-CSM is expected soon, between October 12, 2026 and November 17, 2026.
Is ASUS PRIME B850M-K-CSM still receiving firmware updates?
Yes, ASUS PRIME B850M-K-CSM received a firmware update within the last 3 months. The most recent version is 1804.