Machine Suddenly Runs Very Slow

I have an Asus S406U i7-855u Coffeelake 16GB RAM 500GB SSD purchased in 2018

Currently running 21H2 22000.556

Used mainly for spreadsheets and word processing

It runs like lightning most of the time but occasionally it hits a phase of running like treacle. (twice on Win10 and now once on Win11)

Symptoms are EVERYTHING runs slow: mouse, keyboard, explorer, browsers, menus, all applications

Opening a folder in Explorer takes 5 seconds where it would normally take 0.01 second

In the past this problem usually persists for a few days and then resolves itself spontaneously

Reboots have no effect

There are no symptoms in Task Manager that I can find that would explain what is going on

CPU is not being used by any processes (<3% total)

Memory is not being stretched by any processes (29% used by various processes)

Disk is not active (<1%)

Ethernet and WiFi are not active 0%

GPU is 1%

All windows updates are up to date

All windows optional updates including all drivers are up to date

All virus protection is up to date

Full virus check shows nothing

I tried the benchmark test utility at Home - UserBenchmark

and it says machine is performing way below expectations

UserBenchmarks: Game 3%, Desk 14%, Work 3%
CPU: Intel Core i7-8550U - 12.2%
GPU: Intel UHD Graphics 620 (Mobile Kaby Lake R) - 1.6%
SSD: Sandisk SD8SN8U512G1002 512GB - 25.4%
RAM: Micron MT52L1G32D4PG-107 2x8GB - 24.3%
MBD: Asus X406UAR
PC Status: Overall this PC is performing way below expectations (1st percentile). This means that out of 100 PCs with exactly the same components, 99 performed better. The overall PC percentile is the average of each of its individual components. Use the charts in the benchmark sections of this report to identify problem areas.

How do you identify why a machine is running like treacle?

mojorising said:

it runs like lightning most of the time but occasionally it hits a phase of running like treacle. (twice on Win10 and now once on Win11)

Click to expand...

Sorry no one has answered you sooner. I just saw your post. So this problem carried over from Windows 10. Since it happens so seldom, it would be very hard to troubleshoot in a traditional way. The times it happened, did a restart get the computer running normally again? First, I would run a full scan with Malwarebytes. If this was an upgrade from 10 to 11, the next thing I would do is backup all personal files, then do a clean install of the OS, all updates, and all current drivers because an app, setting, or junk could have carried over from 10. Before beginning to add or change anything after a clean install, run a benchmark test and make note of the results. Repeat a benchmark as you go along in setting it up from there to see if your benchmark changes.

Personally, I never do an upgrade but a clean install if I change OS.. It's a pain, but I like to know I start out clean.

Thanks for your reply Glasskuter

I spent a while analysing Event Logs and I thought I was onto the problem with a system warning about a processor being restricted by the BIOS

The Event Log is a good place to look for anybody who googles this

But anyway, it was a wild goose chase and I ended up using Windows Recovery - 'Reinstall Windows but keep files' option.

This is a glass is half full (you get to keep your files) and glass is half empty (you have to reinstall everything) but it fixed the machine

The system warning about a processor being restricted by the BIOS was still there after the fix but the machine is running fast again.

Is it a laptop or a desktop? computers get slower with age it seems lol.

If a reset fixed it, that's a pretty good indication some piece of software was the culprit. Glad you got it sorted.