Loud fan comes on when playing TS4 on iMac

[sims929292]

Hello, I’m becoming concerned with the fan on my iMac running when I play TS4. It gets pretty loud. I notice it doesn’t run when I’m in CAS or looking through the gallery but it runs when I’m actually in the game playing. It starts right away and just keeps on running.
I did a google search on the issue and most of the answers that I found were related to people with older Macbooks.
Mine is an iMac desktop computer that I purchased in May 2019. I wonder if it’s overheating and this will cause damage in the long run or is it something that won’t cause any problems and I can just ignore it?
The vents are clear and there is nothing under them obstructing them. Also the fan only comes on when playing TS4. Otherwise I have never heard it.
Here is more info about my computer:
macOS Catalina


Version 10.15.4


iMac (Retina 5K, 27-inch, 2019)


Processor: 3.6 GHz Intel Core i9


Memory: 32 GB 2667 MHz DDR4


Graphics: Radeon Pro Vega 48 8 GB
Thank you for any help!

[Bluebellflora]

@sims929292

I have the same Mac as you although with the AMD Radeon Pro 580X 8GB GPU and I can hear the fans ever so slightly when I play but not loudly like I can on my MacBook if I don't elevate it properly.

Do you play in full screen or windowed? The resolution on these iMacs is insane which does mean the game looks stunning but also uses a lot of power which in turn needs a lot of cooling. Try windowed mode and make the window smaller.

[sims929292]

@Bluebellflora 

Thank you for the tip. I normally play in full screen mode. I tried windowed mode today and the fan still came on. What else could I do? Also, If the fan keeps running is it going to be harmful to the computer in the long run? Or is it not going to be a problem at all and I can ignore it? It really gets loud and I mean LOUD which is what got me concerned.

[Bluebellflora]

@sims929292

The fan running is a good thing because it's stopping your Mac from overheating, which is a bad thing. You could lower your in-game graphics options so the game is demanding less from your GPU and processor. If it carries on it may be worth getting Apple to have a look at it when their stores reopen.

[sims929292]

@Bluebellflora 

Thank you again for your response. I won't have time to play again until next week, but when I do I'll mess around with the graphics settings and see if I can get the fan to stop coming on. I'll reply here again next week and report any progress (or lack thereof). Also, good idea to go to the Apple store. If they were open, I'd go tomorrow and figure this out. But in the meantime I'll just see what changing the settings will do.

[Bluebellflora]

@sims929292

No, you NEED the fan to come on. If your fans don't run then your Mac will overheat and die eventually as the hardware will be damaged. What you need to do is try and figure out why the fan is ramping up so much and changing the settings may help - https://bjango.com/mac/istatmenus/. There is a great app here that will tell you the fan rpm. You can also see the temperature of various components.

But, you shouldn't have to lower settings, your Mac should be able to handle the game easily. I found this by simple Googling - https://forums.macrumors.com/threads/imac-2019-problems.2203816/, it wouldn't hurt for you to do a little research with "iMac Radeon Pro Vega 48 overheating" and see what you can find.