Microsoft has released an optional preview update for Windows 11 that promises to make everyday interactions noticeably snappier. The update, KB5089573, is now available for Windows 11 versions 24H2 and 25H2, and it targets three of the most frequently used parts of the operating system: the Start menu, Windows Search, and application launch times. The update also introduces a new “Low Latency Profile” designed to further reduce system overhead and improve responsiveness—making it the most significant performance-oriented Windows 11 preview in recent months.
KB5089573 bears the build numbers 26100.4620 for Windows 11 24H2 and 26200.5110 for Windows 11 25H2. It is a non-security “C” week preview update, meaning it will not install automatically. Users who wish to benefit from its improvements must manually navigate to Settings > Windows Update and select Check for updates. Once the optional update appears, clicking Download and install will begin the process. The update’s main payload weighs in at roughly 680 MB for x64 systems, though actual download size may vary depending on the current state of the operating system.
What’s New in KB5089573
The headline features of KB5089573 revolve around everyday speed improvements. Microsoft’s internal telemetry and feedback from Windows Insiders have long highlighted three pain points: a sluggish Start menu, inconsistent Search performance, and a perceptible delay when launching apps. With this update, the Windows shell team has delivered optimizations that touch all three areas simultaneously.
Start Menu Acceleration
The Start menu in Windows 11 24H2 and 25H2 has evolved significantly since the original 2021 redesign. Despite that, users with large application libraries or heavy customization often report stutters when opening the menu or scrolling through the All Apps list. KB5089573 introduces a lightweight caching mechanism that shifts frequently requested icon assets and metadata into system memory more aggressively. The shell now pre-fetches Start menu tiles when the user approaches the taskbar—a subtle but effective trick that hides milliseconds of latency. On a reference system with a Core i7-14700K and NVMe SSD, the Start menu appears up to 200 milliseconds faster after installing the update, and the “Recommended” section populates nearly instantaneously.
Windows Search Overhaul
Windows Search is perhaps the most complex component touched by KB5089573. Historically, Search relies on an indexing engine that prioritizes resource thrift over real-time speed. That changes here: Microsoft has revised the Indexer’s threading model so that foreground user queries receive a higher I/O priority than background indexing. This means that when you press the Windows key and type, the system immediately shifts resources to deliver results. The search box also benefits from a new caching strategy that retains the last 100 queries in a fast-access buffer, slashing the time needed to re-run a common search. In practice, searching for a document or setting that would previously take 800–1200 ms now resolves in under 500 ms on typical hardware.
Faster App Launches
Application launch speed depends on many factors—disk speed, CPU, memory pressure, and the complexity of the app. KB5089573 doesn’t rewrite the Windows kernel, but it does introduce a smarter pre-loading algorithm that identifies frequently used Win32 and UWP applications. Windows now tracks which programs are launched together in typical workflows and begins staging their DLLs and dependent libraries into the system cache in the background. The result: when you need Photoshop right after Lightroom, or Word after Excel, the second application launches noticeably sooner. Early benchmarks show cold-launch times for Microsoft Office apps dropping by 15–25%, while hot-launch times (when the app was recently closed) become nearly instantaneous.
The Low Latency Profile: A Deeper Look
Accompanying the performance tweaks is a new feature dubbed the Low Latency Profile. Listed in the update’s change log as “Optimize system for low latency in interactive workloads,” this toggle appears under Settings > System > Power & battery > Power mode. Once enabled, it adjusts several low-level parameters:
- Processor performance boost mode becomes more aggressive, ramping up clock speeds sooner when user input is detected.
- Storage stack latency targets are tightened from the default 50 ms to 10 ms, prompting the NVMe driver to complete I/O operations faster—at the cost of slightly higher power consumption.
- Memory compression is temporarily reduced, because de-compressing pages adds micro-latency. Instead, the system prefers to keep a larger standby list, ready to hand pages to applications without delay.
- GPU scheduling shifts toward immediate presentation, ensuring that render frames are not buffered unnecessarily.
Microsoft has caveated the Low Latency Profile as “best for scenarios where responsiveness matters more than battery life,” placing it in a category similar to the existing “High Performance” power plan but with finer-grained controls. On a laptop running on AC power, the profile shaves another 50–100 ms off visible UI transitions. On battery, the trade-off becomes a 7–10% reduction in battery runtime, so the feature is off by default unless the user explicitly opts in.
Build Numbers and Version Specifics
KB5089573 serves two separate Windows release branches:
| Windows Version | Edition | Build Number After Update |
|---|---|---|
| 24H2 | Home, Pro, Enterprise, Education | 26100.4620 |
| 25H2 | Home, Pro, Enterprise, Education | 26200.5110 |
Both branches share the same servicing stack and receive identical improvements. Users on Windows 11 23H2 or older must first upgrade to 24H2 to qualify. The update also marks the first time a performance-centric preview has been offered concurrently for two active Windows 11 versions—a deliberate move by Microsoft to cover its entire supported ecosystem as quickly as possible.
How to Install KB5089573
Because KB5089573 is an optional preview, it will not be force-fed to your PC. To get it:
- Open Settings (Windows + I).
- Navigate to Windows Update.
- Click Check for updates.
- Once the update appears, click Download and install.
- Reboot your PC when prompted.
The installation process typically takes less than five minutes on modern hardware. The system will restart once, and the new build number will be visible in Settings > System > About.
For organizations using Windows Update for Business, the update is available through the usual deferral rings. IT admins can download the standalone MSU package from the Microsoft Update Catalog and deploy it via software distribution tools.
Known Issues and Stability
As a preview, KB5089573 carries the usual disclaimer: it has not been thoroughly battle-tested in all configurations, and Microsoft encourages users to install it only if they are comfortable with pre-release software. A handful of early adopters on the Windows Insiders subreddit have flagged the following glitches:
- On devices with certain third-party shell extensions (notably older versions of Classic Shell and Start11), the accelerated Start menu may fail to render custom tiles, displaying blank rectangles instead. Disabling the extension resolves it, and developers are said to be working on compatibility patches.
- A small number of laptops with Realtek audio chips report a popping sound when the Low Latency Profile is enabled and the system transitions between power states. Microsoft has acknowledged the bug and plans a fix in the next cumulative update.
- Hyper-V virtual machines with dynamic memory enabled may experience unusually high memory pressure when both the host and guest have the update installed. A workaround is to assign static memory to VMs for now.
Apart from these edge cases, the update appears stable. It does not alter security settings or interfere with Windows Defender, and all core applications—Edge, Office, and the Microsoft Store—continue to function normally.
Impact on Users and Enterprise
For the average Windows 11 user, KB5089573 is closer to a “feel” upgrade than a feature upgrade. The perceptible snappiness—faster Start, quicker Search, and snappier app launches—improves daily productivity without altering workflows. That makes it an easy recommendation for anyone willing to run a preview.
Enterprise customers stand to gain from the Low Latency Profile as well. In sectors like finance, computer-aided design, and real-time audio/video production, milliseconds matter. Being able to toggle a system-wide latency reduction without resorting to third-party tuning tools simplifies IT management. The update also aligns with Microsoft’s broader push toward optimizing Windows for “creative professional” personas, who demand consistent low-latency performance.
Gamers may also benefit: while KB5089573 is not specifically a gaming update, reduced input lag and faster app switching can improve the experience in multi-tasking scenarios. The Low Latency Profile does not conflict with the Xbox Game Bar or the “Game Mode” power plan; in fact, they complement each other.
Looking Ahead: Patch Tuesday and Beyond
KB5089573 will likely be rolled into the mandatory June 2026 Patch Tuesday security update, alongside another round of stability fixes. Microsoft’s standard cadence is to use optional preview weeks (the fourth Tuesday of the month) to gather telemetry and user feedback, then fold the proven bits into the next month’s cumulative update. If no show-stopping bugs emerge, the performance improvements introduced here will become the new baseline for all Windows 11 24H2 and 25H2 PCs by mid-June.
Beyond that, sources indicate that the Low Latency Profile will evolve into a full-fledged “Responsiveness Mode” in a future Windows 11 feature update. Microsoft is reportedly investing in machine-learning models that can predict a user’s intent and dynamically adjust latency settings per application—no manual toggle required. That vision is still a year or more away, but KB5089573 plants the seed.
For now, Windows 11 users running 24H2 or 25H2 can grab the update immediately and enjoy a demonstrably faster desktop. As always with previews, remember to back up important data before installing, and keep an eye on the Feedback Hub for any issues that might affect your specific hardware.
KB5089573 underscores Microsoft’s renewed focus on fundamentals. A decade ago, Windows updates were about new features; today, the most impactful ones are about making what you already have feel faster. This preview delivers that in spades.