Windows 11's October update (KB5066835) has caused significant performance issues for gamers, particularly those using Nvidia GPUs, leading to a drop in frame rates from 120–140 FPS to 40–70 FPS. The update has primarily affected systems running Windows 11 versions 24H2 and 25H2, while users on Windows 10 and those using Linux or Steam Deck reported no issues. Affected Nvidia models include the RTX 5000 series and RTX 4080 and 4090. In contrast, AMD graphics card users maintained normal performance levels. The cause of the frame rate drops is unclear, but it may involve conflicts between Windows updates, Nvidia drivers, and game engine interactions. Nvidia released a hotfix driver on November 19, which reportedly restored and even improved performance for some users.