"AK" wrote

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| I put a thermometer in and it read around 100 degrees F.
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Try this:

https://www.cpuid.com/softwares/hwmonitor.html

Unless your system is very old it should work. I'm
not sure offhand, but I think something like 140 is
not unusual for CPU. 100 for hard disks. If you're
worried, look up specs for the actual product. But
sticking a thermometer into the case doesn't tell
you anything. Especially since we don't know whether
the room was 65F or 95F.

If you don't have an extra case fan, that's a good
idea. They're cheap. Most cases will have brackets for
a fan. If not you can just bolt it to the back grid with
the holes. Point it blowing out, so it wll pull air past the
hard disks. Some cases also provide a "chimney" on the
side panel, so you can draw air directly from the board.

When buying a fan there are two basic options. One
is a 3-pin connector that goes directly to the board.
That's good, but you need to make sure you have a
plug for it. (Typically near the CPU.) The other kind uses
the standard 4-pin power connnector coming from the power
supply. That's also fine, but in some cases it might result
in the fan running when the computer is set to sleep.