Check background load after restarting your computer

Your computer feels slow, but it is hard to tell whether the processor is struggling or background tasks are keeping it busy. A restart can stop stuck processes, but it can also trigger updates, file indexing, and cloud sync that take time to settle.

Compare the same processor test before and after restarting. The Processor Test reports single-core and all-core speed, with a score out of 100. The scores are a useful comparison on the same computer, not a list of which apps are using the processor.

Compare processor results before and after a restart

1. Open the Processor Test while the computer is behaving as it normally does. Run the test and note the single-core and all-core scores, along with any slowdown you notice.
2. Restart the computer normally. Sign in, then wait for obvious startup activity, such as an update or cloud file sync, to settle. Give it a few minutes if the fan or drive is still busy.
3. Open the same browser and return to the Processor Test. Keep the computer plugged in if it was plugged in for the first run, and close or leave open the same apps and tabs as before.
4. Run the test again and compare both scores. If one result looks unusually different, wait a few minutes and run one more comparison under the same conditions.

Record the scores and conditions rather than relying on memory. Browser version, power mode, temperature, and other open work can affect a browser-based benchmark. For more context on that last factor, see how background tasks affect CPU benchmark results.

What the result means

The scores improve after the restart

A process or temporary workload may have been affecting the first run. The restart may have closed a stuck app or finished pending work. If the computer also feels more responsive, watch whether the slowdown returns when you open your usual apps.

The scores are about the same

The restart did not make a noticeable difference to this test. That does not prove nothing is running in the background. It means the processor score stayed similar in the two test conditions. The cause of slowdowns could instead be memory pressure, storage activity, a browser issue, or a problem with a particular app.

The scores are lower after the restart

Startup tasks may be using processor time, or the computer may be in a different power state. Updates and cloud sync often start after you sign in. Wait until that work quiets down, then repeat the test. A lower result once is not enough to show that the restart damaged anything.

The scores change a lot between runs

Small differences are normal. Larger swings can happen when another task starts, the browser tab is in the background, or the computer heats up during repeated testing. Close unrelated work, keep the test tab in front, and avoid running other processor-heavy tasks during the comparison.

How to reduce background load

1. Find what is busy. On Windows 11, open Task Manager with Ctrl + Shift + Esc, then check the CPU column on the Processes page. On macOS, open Applications › Utilities › Activity Monitor and select the CPU tab. Sort by CPU use and check whether a familiar app or task is active.
2. Give system work time to finish. After a restart, Windows may be installing updates or scanning files, while macOS may be syncing or indexing. Check Settings › Windows Update on Windows 11 or System Settings › General › Software Update on macOS. Let active updates complete before comparing again.
3. Limit unneeded startup apps. On Windows 11, open Settings › Apps › Startup and turn off apps you do not need to launch at sign-in. On macOS, open System Settings › General › Login Items & Extensions and remove only items you recognize and do not need. Avoid disabling security or system software just to raise a score.
4. Close extra browser work. Close tabs running video, games, or other demanding tasks, and keep the benchmark in the foreground. Use the same extensions and browser settings for both runs so the comparison stays fair.
5. Keep power conditions consistent. On Windows 11, check Settings › System › Power & battery and use the same Power mode for both tests. On a Mac laptop, check System Settings › Battery and keep Low Power Mode in the same state. Also compare plugged-in runs with plugged-in runs, not with battery-powered results.
6. Restart once after changes. If you changed startup apps or completed an update, restart and allow the computer to settle before testing again. Change one thing at a time so you can tell what helped.

What this test can and cannot show

The Processor Test can help you compare CPU performance under similar conditions. It cannot identify a specific background app, read the computer's exact processor temperature, or prove that a part is faulty. Check Task Manager or Activity Monitor to find active processes, and use the score as one clue alongside the slowdown you can actually observe.

If the computer remains slow after startup activity settles, check whether the problem happens in one app or across the whole system before changing more settings.