ASUS updates ROG Crosshair X870E beta BIOS with support for AMD EXPO Ultra Low Latency and new DDR5 timing options
ASUS has published new beta BIOS versions for the entire ROG Crosshair X870E motherboard family. The update, identified with the build number 2305 for most models (and with builds 0915 or 0515 for selected variants), incorporates the AGESA ComboAM5 version 1.3.0.1b and brings three technical changes that directly affect the performance of DDR5 memory and the advanced configuration options available to the user.
The list of models covered by the update is extensive: ROG Crosshair
Support for AMD EXPO Ultra Low Latency, the most relevant change
The most notable novelty of this beta is the incorporation of support for AMD EXPO Ultra Low Latency (EXPO ULL). This technology was announced by AMD during Computex 2026 and allows memory kits certified with this profile to offer a performance improvement of approximately 4% on average compared to standard EXPO kits without the ULL profile. That data is based on AMD tests with a system equipped with a Ryzen 7 9700X processor. The first memory kits supporting EXPO ULL certification are planned from partner manufacturers starting in June 2026.
Along with support for EXPO ULL, the BIOS adds three new memory timing options within the AI Tweaker section, under the DRAM Timing Control panel. The new parameters are called TccdL, TccdL_WR and TccdL_WR2, and correspond to low-level timing controls designed for advanced optimization of DDR5 modules.
These are options aimed at users who perform manual overclocking and want to adjust memory behavior beyond what the automated EXPO or AEMP profiles allow. In the review of the ROG Crosshair
Support for ROG ARCANA DDR5 20TH modules
The update also includes Explicit support for ROG ARCANA DDR5 20TH modulesthe Republic of Gamers 20th Anniversary Commemorative Memory Kit. These modules operate at DDR5-6000 with CL26 latencies and have a capacity of 48 GB. ASUS had already presented them publicly previously, but the inclusion of support in BIOS was the necessary step for the X870E family boards to recognize them correctly and apply the timing profiles automatically without the need for manual configuration.
This beta follows a previous ASUS update for AM5 platform based on AGESA 1.3.0.1which had already incorporated the same DDR5 timing controls to more general models of the X870 and X870E ranges. The difference is that the new published files focus specifically on the Crosshair X870E family, while for the rest of the brand’s models the new files will arrive in the coming days or weeks, according to ASUS’ own statement.
As with any beta update, ASUS does not recommend it as a primary update for users looking for stability in their usual work or play system. It is a version aimed at those who want to test the new features in advance or who have specific hardware, such as the new ARCANA DDR5 20TH kits, which require this firmware to function correctly from the first moment. Users who prefer to wait will see the stable version with these same functions arrive on the official ASUS update channel in a period that usually ranges between two and four weeks from the publication of the corresponding beta, although on this occasion the company has not specified a specific date.
