Ambient Temperatures Effect on PC Cooling

Introduction

In the past, we've had several write-ups that discussed
various aspects of PC cooling, thermal conductivity of components, liquid vs
air cooling and many other. The one topic we have not yet discussed in greater
detail is ambient temperatures, in other words, room temperatures that most
computers operate in. While it doesn't seem like ambient temperatures play a
large role in the system cooling process, they actually dictate various
behaviors of the systems during idle speeds as well as full load speeds.

In a nutshell, ambient temperatures will rise or lower not
only the average idle speeds, but 100% load speeds, therefore one can control
system heat by simply controlling the ambient temperatures.

What does this mean? Well, let's look at some examples:
Suppose that the ambient temperature in your room is 27C. This means that the
lowest possible temperature you can bring your system down to is approximately
27C. If this ambient temperature is a little bit higher due to summer heat or
other reasons, such as 35C, then the lowest possible temperature of the system
would also be around 35C. Why does this matter? Well, if you're reaching high
temperatures during peak loads when ambient temps are relatively low, then this
means the system is very likely to overheat when the ambient temperatures pick
back up.

This is how ambient temperature affect system temperature in
the most basic fashion. However, it also gets a little more complicated than
that. Space is another big factor when it comes to ambient temperatures. A
desktop that is sitting in a wide open room with plenty of airflow will have a
similar delta temperature as the rest of the room. On the other hand, a desktop
that is cramped under or behind furniture is less likely to have the same
temperature. This is mostly because in tight spaces, hot air that is pushed out
by the system tends to “stick around” thus raising the overall ambient temps
which in return raise the overall system idle and load temps. If your system is
tucked away in a cupboard or other tight spaces, if there are cloths covering
the system or its vents, then the ambient temps around the system will go up.
The sooner you free up the system and put it in relatively open space, the less
likely your system is to overheat. Systems that are obstructed also have poor
airflow, so not only is the air coming in hotter, but also comes in and out
much slower than usual. Therefore under load, system temps will significantly rise.

In order for systems to be in constrained spaces such as
closets or cupboards, they must have much faster, more robust fans that can
move a lot of air and keep the cooling efficient. Regular desktop fans are only
good when the ambient temperatures are reasonable.

Liquid cooling systems are less susceptible to the changes
of ambient temperatures, although they are still affected in the long run. For
example, liquid system relies on water circulation to keep the heat away from
the CPU/GPU and other components. It travels to the radiators where surface
area and air turbulence are combined to cool off the water. Ambient
temperatures usually affect what happens at the radiator, but because this
process happens later in the loop, temperatures at the CPU/GPU tend to remain
relatively low. It's recommended to use water cooling for scenarios where
proper airflow and ambient temps are an issue.

Most cases today have very well optimized airflow, as long
as nothing is blocking the intake portion of the case. Most cases will intake
air from the front or the bottom and expel it out the back or the top. These
areas must be kept open and unobstructed otherwise the overall ambient
temperature in the case will rise.

It's also recommended to keep the system in a cool, well-ventilated
area. During winter, this may not be possible simply because heaters are typically
working and are blowing hot air around the system. However, positioning the
system away from heat vents can help with the overall case temperatures.

As we can see, ambient temperatures are important to
consider when taking into account the amount of heat your system is producing. Keep
the ambient temperatures low and you'll keep your PC happy. If the temperatures
are high, you can use some of the suggested remedies to bring the temperatures
down. Of course, if there are other heating issues inside of the case such as
poor airflow, dust, lack of good contact or proper thermal compound, then those
issues need to be addressed as well.