Recent performance reviews have highlighted significant issues with Windows 11 version 24H2 compared to 23H2, particularly concerning the Intel Ultra 9 285K CPU. Initial tests included both in-place upgrades and clean installations, revealing minor performance differences but with some unexpected results.
Performance issues reported with Windows 11 24H2 on Intel Ultra 9 285K CPU
Some users have reported severe issues following recent Windows patches (KB5050094/KB5051987), leading to game crashes. Neowin forum member kiddingguy documented these issues. Additionally, Borncity shared a troubling report from a user experiencing a persistent bug that could severely hinder performance unnoticed.
The user, running Windows 11 on an Intel Ultra 9 285K CPU within an ASRock system, noted that the operating system enters a power-saving mode when applications are minimized, resulting in significant CPU throttling. This behavior was confirmed through tests conducted using Prime95 and 7-Zip benchmarks, where the CPU showed lower usage and clock speeds when tasks were not in focus.
Microsoft officially supports the Intel Ultra 9 285K on Windows 11 24H2, according to its CPU support list. However, the affected user observed that similar problems did not occur with the Intel i9-12900K or AMD’s Ryzen 9 9950X, the latter of which is not included in Microsoft’s support list for this version.
Do NOT update Windows 11 if you like using File Explorer
This discrepancy in performance may explain why earlier reviews, including those featuring the Intel 14700K, did not report similar issues, as this model shares architectural similarities with the 12900K, retaining hyperthreading capabilities.
Borncity’s coverage included a reader’s report detailing performance problems specifically with the Intel Core Ultra 9 285K CPU on an ASRock Z890 Pro RS motherboard, which faced issues starting Windows 11 24H2 prior to installing the latest beta BIOS (MCU 116). The BIOS update addressed startup errors linked to the CPU and Intel microcode.
Rüdiger, the user who reported these issues, found that performance problems arose when Windows 11 24H2 was paired with new Intel Core Ultra 200 series CPUs. The CPU throttling was substantial, causing performance to drop significantly once applications lost focus. Rüdiger documented these findings with screenshots illustrating the difference in CPU performance when tasks were minimized versus active.
Attempts to distribute the application’s workload across all cores did not alleviate the problem. Rüdiger discovered no alternative solution besides enabling the maximum performance energy-savings plan, which allowed affected applications to maintain higher CPU performance in the background.
Additionally, Rüdiger noted that performance issues were absent on systems with AMD Ryzen 9 9950X or Intel Core i9-12900K CPUs. Another problem identified since upgrading to Windows 11 24H2 involved various USB sound cards entering a power-saving mode, causing delayed sound output for 10-15 seconds after pausing media.
Following the February 11, 2025, security updates, users reported complications with Core Isolation and Memory Isolation settings disappearing and difficulties installing signed drivers. Rüdiger indicated that certain Lenovo BIOS updates failed due to driver loading issues, with older USB sound drivers becoming incompatible post-update unless installed beforehand.
Featured image credit: Kerem Gülen/Imagen 3
