Review I've been using a PC without case fans for over a year. Here's my experience.

[Dantido]

Mhm. You heard that right. During all my time in PC gaming, I've never used a single case fan.
Why? Well, I started PC gaming with an extremely old PC that I inherited. It ran much faster than what I was used to see on a desktop, though its components were quite obsolete and had fans that were almost going to break.
After I changed the motherboard, sold the HD 5400 GPU it had and threw the i5 860 in the garbage (simply because it was impossible to sell, since it was extremely hot, bottlenecked even the most low-end GPUs and couldn't be overclocked at all), I ended up with the system I have today, which has a GTX 1060 6GB, a B450 Aorus Elite, a R5 2600 and a pretty decent 250GB Jaguar SSD.

The only thing I didn't change, however (apart from the HDD, which was pretty good) was the case, simply because it seemed to work pretty well as it was big enough to store all the components.
The case is so old I don't even know the exact model. I only know that it's an old school PrimuX black case. It has no dust filters and no vents on the top side. However, the thing I figured out today that shocked me is that the case has no support for case fans, so it has zero intakes and zero exhausts!
Why did this shock me, you ask?
Well, my temps were completely normal, even without the case fans! Here are some of the temps I've got during my gaming sessions and some other stress tests (all of this done in a 24-26ºC ambient temp) :

Unigine Heaven : For this, I simply went into walk mode and stayed in an area where I had the least amount of FPS (47). Then, I waited 30 minutes and came back. The GPU was at 71-72ºC and the CPU was at 54-56ºC.
Furmark : I personally don't like this tool as it gives unrealistic loads to the GPU. That's why I, to make things a bit more realistic, simply left it on stress test for 5 minutes. The final temp was 74ºC.

Now, for the games :
The Witcher 3 maxed out with mods (Phoenix Lightning+HD Rework+4K Grass/Clouds and a ton more) : With all these graphical mods the game looks fantastic, and even though many of these mods don't impact the framerate, some of them do.
I simply went into Toussaint's cementery, a place where there's a dense forest that tanks FPS due to the Ultra configs of TW3.
After 20 minutes the GPU ended up at 75ºC and the CPU at 58ºC.
GTA V : With everything on Ultra besides MSAA, which is at 2X, and Grass quality, which is at High, the temps were quite cool overall, but varied a lot depending on the area I was.
In Los Santos, it peaked at 65ºC, but it was mostly at 63ºC.
In forest areas, it peaked at 72ºC-74ºC, though during normal gameplay I've never seen it go over 71ºC, even when playing during Trevor's missions, that often occur in areas with a lot of forest.
The CPU was, again, at a pretty similar temp as before.

Now, what is my conclusion? Case fans are not a requirement.
They're a nice add-on, of course. I actually had more problems with hot air accumulating inside my case (and thus, for example, if I went into a low-req area, then to a high-req one, and let the GPU get hot, if I return to the low-requirement area I will get higher temps. This happened in TW3, since once I returned to Toussaint after the test, my GPU wouldn't go below 70ºC, even though the temps there are usually lower).
However, it's not the end of the world, as you can see. The hot air problem isn't that much of a deal since one can simply wait on the pause menu of a game for a bit, which is usually much less demanding than the game itself, for the hot air to be dissipated by the GPU and CPU.
I'll buy a new case with case fans once the market stabilizes again, though, because the hot air problem is a bit hard to deal with during the summer.

(Sorry if I tagged my thread wrong, by the way. It's my first day on the forums and I'm not too sure if I picked the correct one for this).

 

[CountMike]

Mhm. You heard that right. During all my time in PC gaming, I've never used a single case fan.
Why? Well, I started PC gaming with an extremely old PC that I inherited. It ran much faster than what I was used to see on a desktop, though its components were quite obsolete and had fans that were almost going to break.
After I changed the motherboard, sold the HD 5400 GPU it had and threw the i5 860 in the garbage (simply because it was impossible to sell, since it was extremely hot, bottlenecked even the most low-end GPUs and couldn't be overclocked at all), I ended up with the system I have today, which has a GTX 1060 6GB, a B450 Aorus Elite, a R5 2600 and a pretty decent 250GB Jaguar SSD.

The only thing I didn't change, however (apart from the HDD, which was pretty good) was the case, simply because it seemed to work pretty well as it was big enough to store all the components.
The case is so old I don't even know the exact model. I only know that it's an old school PrimuX black case. It has no dust filters and no vents on the top side. However, the thing I figured out today that shocked me is that the case has no support for case fans, so it has zero intakes and zero exhausts!
Why did this shock me, you ask?
Well, my temps were completely normal, even without the case fans! Here are some of the temps I've got during my gaming sessions and some other stress tests (all of this done in a 24-26ºC ambient temp) :

Unigine Heaven : For this, I simply went into walk mode and stayed in an area where I had the least amount of FPS (47). Then, I waited 30 minutes and came back. The GPU was at 71-72ºC and the CPU was at 54-56ºC.
Furmark : I personally don't like this tool as it gives unrealistic loads to the GPU. That's why I, to make things a bit more realistic, simply left it on stress test for 5 minutes. The final temp was 74ºC.

Now, for the games :
The Witcher 3 maxed out with mods (Phoenix Lightning+HD Rework+4K Grass/Clouds and a ton more) : With all these graphical mods the game looks fantastic, and even though many of these mods don't impact the framerate, some of them do.
I simply went into Toussaint's cementery, a place where there's a dense forest that tanks FPS due to the Ultra configs of TW3.
After 20 minutes the GPU ended up at 75ºC and the CPU at 58ºC.
GTA V : With everything on Ultra besides MSAA, which is at 2X, and Grass quality, which is at High, the temps were quite cool overall, but varied a lot depending on the area I was.
In Los Santos, it peaked at 65ºC, but it was mostly at 63ºC.
In forest areas, it peaked at 72ºC-74ºC, though during normal gameplay I've never seen it go over 71ºC, even when playing during Trevor's missions, that often occur in areas with a lot of forest.
The CPU was, again, at a pretty similar temp as before.

Now, what is my conclusion? Case fans are not a requirement.
They're a nice add-on, of course. I actually had more problems with hot air accumulating inside my case (and thus, for example, if I went into a low-req area, then to a high-req one, and let the GPU get hot, if I return to the low-requirement area I will get higher temps. This happened in TW3, since once I returned to Toussaint after the test, my GPU wouldn't go below 70ºC, even though the temps there are usually lower).
However, it's not the end of the world, as you can see. The hot air problem isn't that much of a deal since one can simply wait on the pause menu of a game for a bit, which is usually much less demanding than the game itself, for the hot air to be dissipated by the GPU and CPU.
I'll buy a new case with case fans once the market stabilizes again, though, because the hot air problem is a bit hard to deal with during the summer.

(Sorry if I tagged my thread wrong, by the way. It's my first day on the forums and I'm not too sure if I picked the correct one for this).

You don't have particularly hot components, that's why.