Microsoft’s KB5089573 update brings the Low Latency Profile (LLP, a new responsiveness feature) to Windows 11, and the company says it makes the Start menu, Search, and Action Center up to 70% faster while cutting app launch times by 40%. Those gains come from a blunt trick: a burst of maximum CPU frequency lasting one to three seconds, fired the instant Windows senses you are about to wait.
The speed-up is real on screen. It also sidesteps an awkward question, which is why a 2026 operating system needs a processor sprint to open a menu that took milliseconds on a decade-old machine.
Where the 70 Percent Speed-Up Comes From
Modern laptops and desktops run their processors on dynamic voltage and frequency scaling (DVFS, the system that constantly trades clock speed for battery life and heat). When you click Start, the CPU is usually idling at a low clock to save power, and it ramps up gradually. That ramp is invisible most of the time. It is very visible when a menu hesitates for a beat before it paints.
LLP changes the ramp for short, user-facing moments. When Windows detects an interaction it thinks might stutter, it tells the scheduler to push the relevant cores to top frequency immediately, hold for one to three seconds, then drop back to normal power behaviour. The work finishes inside the burst, so the menu or app feels instant.
The mechanics matter because the published numbers describe perceived snappiness, not new efficiency. Microsoft documents the underlying power controls in its processor power management settings for Windows, and LLP is a targeted override on top of them rather than a rewrite of the code paths that were slow.
| Behaviour | Standard frequency scaling | Low Latency Profile |
|---|---|---|
| Trigger | Sustained workload demand | A specific UI interaction Windows predicts will lag |
| Frequency response | Gradual ramp over many milliseconds | Jump to maximum frequency at once |
| Typical duration | As long as the load lasts | One to three seconds, then back to idle |
| Design goal | Balance power, heat, and throughput | Hide latency on a single user action |
The Cheating Backlash and a Race-to-Sleep Defense
When Microsoft previewed the feature earlier in May, a chunk of the enthusiast crowd called it a hack. The argument went that boosting the CPU just to open a flyout is a confession of bad engineering, and that on a laptop those repeated bursts would quietly eat battery life. The phrase “cheating” showed up across forums and developer threads.
Scott Hanselman, a vice president on the Windows developer team, pushed back hard on X, leaning on a concept engineers call racing to sleep. The idea is that finishing a task at full speed lets the processor return to its deep idle state sooner, so the total energy spent can be lower than dragging the same task out at a middling clock.
Everything is a conspiracy when you don’t know how anything works.
That was Hanselman’s blunt summary of the backlash. His longer point was that macOS, Linux, and mobile operating systems have boosted clocks for interactive moments for years, and that Windows was the laggard here rather than the innovator. Early testing he and others cited showed a negligible change in battery draw, because the extra watts per burst are offset by the faster trip back to idle.
Whether that holds across thousands of bursts a day on cheap thermally limited laptops is the open question. The defense is technically sound. It also does not answer why the bursts became necessary.
Windows K2 and the Admission Behind the Boost
LLP is the first shipping piece of Windows K2, an internal program Microsoft assembled in the second half of last year to rebuild trust in Windows 11. K2 is not a version of the OS. It is an ongoing effort built on three stated tenets: performance, craft, and reliability.
What Microsoft Concedes
The interesting part is what the program admits. In documentation viewed by the press, Microsoft acknowledges it let speed slip in File Explorer, in games, and in basic system UI such as context menus. A company does not stand up a multi-year quality initiative unless it agrees something went wrong, and the same complaints about sluggishness and feature bloat have followed Windows 11 since launch.
Part of that bloat is the steady push of AI surfaces into the shell. The pattern is visible in moves like the walk-back of a Copilot taskbar button users never asked for, and the return of a Copilot docking sidebar that Microsoft had removed a year earlier. Features arrive, annoy people, and get partly reversed.
What K2 Promises Next
The roadmap goes well past a CPU burst. Microsoft is rebuilding the Start menu to be 60% faster and more responsive, adding instant file-name search in File Explorer, trimming memory use, and weighing the removal of ads baked into the interface. For gaming, the company has openly named SteamOS as the bar it wants to match. Read together with smaller quality-of-life fixes like letting users remap the Copilot key, the message is that fundamentals are back on the priority list.
What Else KB5089573 Bundles In
The responsiveness headline buries a fairly large preview update. KB5089573 ships around 30 changes and lifts Windows 11 25H2 and 24H2 to builds 26200.8524 and 26100.8524. Beyond LLP, the notable additions and fixes include:
- Shared audio, letting two people listen to the same output from one Windows 11 PC at once
- Better Task Manager visibility into NPU (neural processing unit, the AI accelerator on newer chips) activity
- Search results that appear after you type as few as two characters
- A fix so Task Manager stops overstating CPU speed on virtual machines after hibernation
- Reliability improvements for File Explorer, USB devices, and the sign-in and lock screens
- Resilience against apps that keep the sensor hub awake and drain the battery
The full list sits in the KB5089573 release notes on Microsoft Support. Because this is a non-security preview, it is optional this month and folds into the next Patch Tuesday for everyone else.
Turning On Low Latency Profile Before Microsoft Does
Installing the update does not guarantee the feature switches on. Microsoft is gating LLP behind a controlled, server-side rollout, there is no toggle in Settings, and once the company flips it for your device it simply runs in the background. Many people will get the bits without the behaviour for weeks.
Impatient users have a workaround through ViVeTool, a community utility that flips hidden Windows feature flags. Microsoft does not support it, so the trade is immediate access against running an unofficial tool. The rough sequence:
- Install KB5089573 from Settings, Windows Update, Advanced options, Optional updates.
- Download the open-source ViVeTool feature-flag utility and extract it to a simple folder such as C:\ViVeTool.
- Open Command Prompt as administrator and run the enabling commands for the LLP feature IDs.
- Restart the PC, after which the profile runs automatically with no further input.
For most people the smarter move is patience. The official rollout costs nothing, carries no risk, and is only a question of when Microsoft reaches your machine.
Frequently Asked Questions
What Is the Low Latency Profile in Windows 11?
It is a feature in KB5089573 that briefly pushes the CPU to maximum frequency, for one to three seconds, when Windows expects an interaction such as opening the Start menu or Search to feel slow. Microsoft says it makes flyouts up to 70 percent faster and app launches 40 percent quicker.
Does Low Latency Profile Drain Laptop Battery?
Microsoft says the impact is negligible. The reasoning, called racing to sleep, is that finishing work at full speed lets the processor drop back to deep idle sooner, roughly offsetting the extra power of the burst. Independent long-term testing on budget laptops is still thin.
Is KB5089573 a Security Update?
No. It is an optional non-security preview update for the end of May 2026. Its changes are expected to roll into the following Patch Tuesday security release, which is when most users will receive them automatically.
Why Is Low Latency Profile Not Turning On After I Install It?
Because Microsoft enables it gradually through a server-controlled rollout rather than at install time. There is no Settings toggle, so a device can have the update for weeks before the feature activates in the background.
Which Windows 11 Versions Support It?
KB5089573 targets Windows 11 versions 24H2 and 25H2, with the update also referenced for 26H1. The update raises 25H2 and 24H2 devices to builds 26200.8524 and 26100.8524 respectively.
Is Using ViVeTool to Enable It Safe?
ViVeTool is a widely used open-source utility, but Microsoft does not support it and enabling unreleased flags can cause unexpected behaviour. The cautious choice is to wait for the official rollout, which arrives at no cost and without modifying system flags.
