If it's a Windows 7 laptop, I'd get a new one.

https://www.microsoft.com/en-us/windows/windows-7-end-of-life-support-information

Blow the dust out of the fan if there's an accumulation. Friend gave a laptop to me some years ago with a cooling/fan platform, said it sometimes overheats ... not after I blew out the cat hair.

No, not Win7, No cat, but I'll try the blow-out. That's what the cans of air are for, huh?

Another thing easily checked is processor usage. I'm not a Windows person but if you go into task manager or whatever it's called now, you might find that a process is using 100% of your processor.

https://www.computerhope.com/issues/ch002001.htm

That could explain the slowdown and the excess heat.

Does the fan sound like it's working hard? Spins faster and louder after it slows down?

Have you scanned for malware?

You could always use it as an excuse to get a new one. :)

"So is it worth having a new fan installed? Will that buy me time or should I get a new computer now anyway? There's nothing latest and greatest than makes me want a new one anyway."

No, I wouldn't spend a cent on repair or part replacement of an old PC. Would you pay for a new paint job for a 15 year old car, a Plain Jane model, that runs rough, burns oil, and needs tires?

As for what would make you want to buy a new one, it would be for the convenience of one that doesn't get sluggish, doesn't have to be turned off periodically, doesn't make you wonder if it might start smoking some day.

I recently scrapped and replaced a couple of PCs whose performance had slowly slipped. I didn't realize it until using two new PCs I purchased for my wife's use. With solid state drives, more memory, and faster processors. After using hers, I realized the ones I used had gotten sluggish and less pleasant to use than her new ones. I have new ones now too, I should have dumped the older ones much sooner.

A serious cleaning is in order - blow it out as best you can. And agree with the above - if it's Win 7 or XP time for an upgrade,

I already said, no, not Win7 or XP.

I used a regular air compressor with a blow gun attachment ... carefully to avoid potential damage from excess force.

If you want to be minimize chances of a recurrence, take off the case -- usually a very simple thing that's described in the owner's manual -- and inspect inside to see how well it is cleaned out.

Alot of the muffin fans on my very old computers would go dry and need alittle 3-in-1 oil, tho to do this would be very difficult on my newer slim-form desktops -- fans are practically inaccessible.

This is a laptop. And it's working very well this morning.

sushipup- Sorry I missed that point. It’s of course possible to open a laptop case, but more trouble than a desktop. Glad it’s still running fine.

Sometimes I post too late at night... ;-)

I understand!

The blow out did a good job, and problems seem to be fixed. I am quite relieved. Thank you all.

Depending on your settings, your history file (in your browser) could have grown to a huge file. If so, this needs cleaning. You can manually clean it if you wish to retain certain items. The history file contains URL addresses of all the sites you have visited.

The cookie file may need cleaning out. A few cookies might be useful, but for the most part, these are junk.

Cache cleaned regularly. It obviously was the dust, now working 100% better.

The term "bug" was coined in the early days of printed circuit boards and shrinking electronic circuits. A researcher had assembled an electronic device and it had strange erratic behavior. When he opened the case, he found an insect crawling over the board. When describing the problem, he stated that the circuit board had a bug, and the term stuck; It became part of electronics language.

According to this item from an IEEE publication, the term was first used by Thomas Edison in the 19th century, long before printed circuit boards:

Edison and "bug"