I like @wpns's answer but to add:
Most likely causes to slow performance:
- CPU
If too much CPU is utilized, resources for processes will be scarce. You say that you don't see any process using 100% of CPU but is the CPU 100% in use? Lots of small tasks could collectively eat up the CPU.
Security applications like antivirus are frequently a cause for performance problems. Take note if you have scheduled scans during the times you have issues. Try to schedule scans for periods when you're not using the machine. Some applications allow you to temporarily disable their features which would allow you to confirm if they are the problem. I would take care in doing so, you may wish to disconnect your machine from the internet before disabling security features.
If a CPU gets too hot, it will also deliberately throttle down the performance (at least chips made since around 2002). If the machine is getting warm from the environment, or the fans are not working well, or the heatsinks are clogged with dust, you could be experiencing performance issues from throttling. There are a number of utilities that can read the temperature for the CPU, some BIOS will also report this information. Appropriate temperatures for your machine will vary wildly based on design but I'd say anything above 50-60C would be too hot.
- RAM
If a machine doesn't have enough RAM available, it will begin to use more and more Virtual Memory which is when hard drive space is used for memory. Hard drives are much slower than RAM and this will cause the machine to slow. The more RAM is used, the more this will begin to affect your performance. A computer will try to optimize virtual memory to reduce access and put more frequent items on real RAM and less frequent in HD. An access to virtual memory is called a 'hard fault' and the number of them can be seen in the task manager. Higher numbers of hard faults are bad. You should not see the number above 10 in normal operation.
It's worth noting that your computer may seem like it has a lot of RAM available but Win10 uses RAM in 'special' ways. Greater than 75% usage of your system RAM will trigger special conditions on your machine. You can also see the 'real' RAM usage under 'commit' in task manager, the number will often exceed the physical RAM in the system.
As @wpns said, applications frequently have tiny errors that can 'waste' RAM over time. A reboot of the system will usually resolve that issue. If you're experiencing a daily problem, your issue is more severe than average however. Take note if you have this problem more often with certain applications.
- Hard Drive
When a hard disk performance falls, this can make virtual memory issues worse. However, a hard disk issue can be bad even when RAM is available. Certain applications and portions of the OS are designed to read from HD under normal conditions. This can cause slow performance if HD performance is bad. A failing HD will often cause very long delays. MS Word will automatically save your working document to recovery every 10 minutes by default. When this occurs, you could see long delays before your system responds if HD performance is bad. Use a utility such as SMART or CrystalDisk to examine the performance of your HD.
- Misc.
Extra applications, intentional or unintentional (adware, spyware, malware), can cause 'hidden' delays on your system. Sometimes it's not possible to see an application's impact from task manager. In some cases, the operating system itself can be corrupted and cause problems.
You can diagnose some of these issues by putting your machine into minimal start (using msconfig), safe mode, reinstalling your operating system, or running a temporary live boot cd (knoppix, ubuntu) and seeing if your machine behaves similarly in those modes.
I once had a machine that would refuse to run correctly with Windows installed but ran fine with Ubuntu. I never figured out why and decided it wasn't worth my time since it was just an internet browsing laptop.
Best of luck with your search!
2
First, i would check your temps. Use a software such as RealTemp to check this. If the temperature is high, open the laptop and check that the internals are clean and dust-free. If they aren't, use some compressed air to clean it.
– NiallUK – 2019-06-13T08:05:13.2801Another thing to fo is look at swap and disk IO. Also, if you reboot does the problem go away? (memory leak?) – davidgo – 2019-06-13T09:05:15.193
@NiallJones, I will try this. However, I don't think it is a dust issue as the laptop is only a month old. However, I do think the laptop might be heating up and causing the cpu to throttle, but need a way to confirm this suspicion. – oshirowanen – 2019-06-13T18:25:13.570
@davidgo, yes a reboot fixes the issue for a few hours. What's the easiest way to see what is causing a lot of swap/disk io activity when the laptop is being very unresponsive? – oshirowanen – 2019-06-13T18:26:40.257
1Sounds like a memory leak to me. Im a Linux person, so not in a position to advise how to check disk IO in Windows - although many laptops have a disk indicator you can use, and I expect the task manager must show swap, memory and CPU usage? – davidgo – 2019-06-13T19:36:13.810
Compare in Task Manager the Performance tab, before and when it happens. – harrymc – 2019-06-16T20:00:27.807
Since a reboot fixes it temporarily, it doesn't sound like overheating. It sounds like you've tested disabling some but not all background processes. Do a clean boot (Microsoft components, only), and see if that makes a difference. Ensure that you do not have two anti-virus programs running concurrently. That will cause this kind of issue. If there is only one, disable it and see if that makes a difference. If so, change to a different AV program. If after all that you still have the issue, and it happens only with MSWord, it's possible that Word is corrupted. (cont'd) – fixer1234 – 2019-06-18T22:38:15.683
I've been away from Windows and Word for awhile, but it used to have some cleanup options. One was going to Uninstall Software, and MS Office had an option there to clean up problems. The Microsoft web site also used to have a Fix-it utility there. If none of those help, uninstall and reinstall MS Office. But before going that far, rule out a corrupted document or template (is the problem with just a specific document? Just recent documents?). If the problem is with any and all documents, there could be a corrupted main template. (cont'd) – fixer1234 – 2019-06-18T22:38:36.057
Try very old documents. Try creating a new document with some other, very different, template that isn't likely to be built on top of the main template, like say one for something like a greeting card. Try Office Online with the problem documents. Install the free WPS Office, which is extremely compatible, and see if you have the same issue with the problem documents. If these steps don't solve it, they will rule out some likely causes. – fixer1234 – 2019-06-18T22:38:41.787
Repeat: Compare in Task Manager the Performance tab, before and when it happens. Please take screenshots of the two and let us have a look. – harrymc – 2019-06-19T06:19:37.997
@oshirowanen, a good answer that solves your problem will require the detail from what has been asked and suggested in comments. You've already invested in a bounty. Maximize the benefit by updating the question in response to the comments. – fixer1234 – 2019-06-20T17:10:50.400
@fixer1234: The post can be considered as abandoned. Current answers throw everything possible at it except the kitchen sink. Hilarious. – harrymc – 2019-06-21T08:02:32.513