Case Fans and Cable Management, How Important Are They?

konsole

Member
About a year ago I ran some tests in Skyrim to get my PC up to temperature and tried some different case fan setups. My case is an older Foxconn case and only has mounts for 2 x 80mm or 2 x 92mm case fans. So is it the best test subject? Probably not but whatever. I tried various tests with those 2 fans with the typical front lower intake and rear higher exhaust. With Speedfan I tried running them in all combinations ranging between off and 100%. Surprisingly I found out that there wasnt a big difference in overall system temperatures in the various case fan setups. The lowest temperatures where achieved having the rear exhaust running at 100%, but it seemed that the front intake made very little difference. The rear exhaust running at 100% instead of off dropped the CPU and GPU temperatures a few degrees celcius each if I remember correctly. However the front intake running at 100% instead of off only had an effect on the System and Hard Drive temperatures a few degrees celcius each. My system does have a top mounted PSU with a down facing fan, so the PSU is most certainly exhausting some of the system heat. The tests I ran tempted me to run just a single 92mm exhaust fan with no intake, and the temperatures during that time seemed fine. I decided to add back in an intake fan because it did have a very small affect on some temperatures, and its an unused mounting point so why not. Currently I'm running 1 x 80mm intake on the lower front, and 1 x 80mm on the upper back, and here is some idle (with light use) temperatures in an 82 degree fahrenheit room...

(in celcius)
GPU - 41
CPU - 35
Core 0 to 3 - 35 average
System - 36
Hard Drive - 34

Remember my room is 28 celcius, so the average temperature across all 5 areas of my PC are running at only 8 degrees celcius above room temperature, or 15 degrees Fahrenheit. BTW, before you say that 80mm fans are too loud and that larger fans can be run slower and quieter and push the same amount of air, the 2 fans I have are Enermax Enlobal fans that run very quiet even at 100% speed that I am running them.

I know we all want to keep our PC's running as cool as possible, even if lower temperatures may not be beneficial to hard drives, but how much do case fans really matter? The main components of heat creation in a common PC are the CPU and GPU, but most of the time these components have their own heatsinks and fans which are probably responsible for almost all of their cooling. Hard drives create some of the system heat, but like I said its debatable that cooler temperatures are even good for a hard drive. If hard drives were negatively affected by elevated temperatures then it would probably be alot more common to see hard drives with built in heatsinks and fans. The PSU also creates some of the heat, but PSU's are usually mounted so they dont increase system temperatures. When the PSU fan is included then thats already 3 cooling fans inside a common computer before any case fans are added. It seems to me that as long as your CPU, GPU, and PSU all have operating cooling fans, then really 1 single exhaust case fan on the upper section of the back panel is probably plenty to exhaust out that CPU and some of that GPU heat. Then if you want to add an intake fan on the lower front it can have an affect, but its very minimal.

My tests probably werent perfect and there are certainly plenty of varying case designs and fans setups and all that, but have you guys done any temperature testing to find out how much your case fans matter?

Linustechtips has 2 videos, 1 in which they test case fans setups, and the other in which they test cable management. The conclusion is that anything more then 2 or 3 case fans has very minimal effect on cooling. In terms of the cable management, they shoved so much crap inside the computer and where finally able to raise system temperatures by filling almost every void with things that should have blocked the air. Anything less then jam packing the computer full of crap and the temperatures werent affected.

I'm just curious to hear from people that feel that having more then a few case fans is worth it, or that water cooling especially is worth it. Being very careful with temperatures when overclocking is understandable, but how many of you use more then a few case fans or use water cooling in non-overclocked systems?

I see people who make it a top priority to organize cables extremely well, and I know some of you do extreme cable management simply for aesthetic reasons, but I know many people do extreme cable management because they think it has a noticeable affect on temperatures. When I'm talking "extreme" I mean tying cables together tightly and tucking them into any nook and cranny available especially behind the motherboard making sure there is no slack in any cable. Less extreme cable management I would consider doing a small amount of tying cables together and some pushing of the cables into unused areas of the case. Removing excess cables from a modular PSU I would consider "less extreme" cable management. Have you ever tested cable management to see how much it affects temperatures?
 
Last edited:

konsole

Member
If those are your temps, why are you even worried? Those are very good temps.

I'm not worried about the temperatures I'm getting, I'm just pointing out that I seem to be getting good temperatures on minimal case fans and less then extreme cable management. So I was curious as to why other people think that more then a few case fans, and extreme cable management has much of an effect on lowering temperatures?
 

porterjw

Spaminator
Staff member
Even with one intake fan and one exhaust fan, it's likely there's enough airflow through the case to keep things cool even with a rat's nest of cables. That being said, the smoother the path there is through the case, the quicker it will flow. If there's a rat's nest of wiring in there, you won't necessarily have 'hot pockets', but the obstructions create turbulence, which in turn slows the flow rate (and could possibly increase the noise level a bit).

Cable management doesn't have to mean everything is perfect - bunching a group of them together and using one zip tie to keep everything out of the direct flow path is what some people do. I think the folks (myself included) that spend a far much longer time than needed, trying several different layouts and going through dozens of zip ties, making sure everything is near-perfect do so because they either want something that looks nice sitting on their desk (windowed cases), or are simply OCD (again, myself included).

Also, a system with at least some amount of cable management is far easier to work on should a hardware problem arise.
 

Darren

Moderator
Staff member
Aesthetics and why not take a little time to make it look nice. Alot easier to have passion out of your build if it looks moderately clean than a bundle of snakes crammed in your case.
 

Darren

Moderator
Staff member
If done correctly it also makes it so much easier to work inside if you ever change any parts out.
I'll sometimes get customers with custom builds and just completely redo their cable management because it's so bad and is interfering with working on it.
 

konsole

Member
So far the comments seem to be geared towards aesthetics and ease of maintenence being the reason for cable management. I havent seen any comments about how much cable management affects termperatures, or atleast how they have tested for this. Aesthetics and ease of maintenence aside, there is still plenty of talk out there about cable management having an affect on temperatures, and in general the claim is that the more extreme the management the more extreme the temperature decrease. I'm curious to find out how many people have actually tested that claim. I would think extreme cable management certainly wouldnt raise temperatures, but if the best its going to produce is a 1 to 2 degree drop in temperatures then is that really enough to say that decreased temperatures is one of the reasons for doing it?

Something else about extreme cable management that keeps me from going too far is the added stress on cables and connections. Extreme cable management usually involves some level of placing sharp bends somewhere along the cables or even at the cable connections. It may not be all that likely that this would cause a failure, but I'm sure that as the cables insulation becomes less pliable over time due to age, that the possibility of failure would increase over time. Leaving cables bent at such extremes for long enough would also mean they would less willing to bend back to straight or to the opposite angle should the need arise in the future. That resistance to bending back along with the less pliable insulation from age could result in tearing the insulation. This may all be worrying too much, but I think its atleast another factor to consider especially if your someone would doesnt do a major upgrade every year or two.

I'll leave water cooling alone because I dont have it and probably will never get involved with it, so I have no personal experience to go by.

So what about case fans? Have any of you tested all the claims surrounding case fans? Claims like... more fans equals more cooling, small fans arent effective (80/92mm), more expensive fans are better at cooling, etc.
 

konsole

Member
Yes thanks Darren, those are the 2 videos that I referenced in my original post. The conclusion he got from the cable management test is that you are unlikely to experience anything more then an extremely small difference in temperatures when comparing extreme cable management with very bad cable management. He had to go as far as effectively blocking all fans "and" filling all empty spaces with something, which insulated those components and didnt give them any surrounding air to radiate their heat off to.

The conclusion he arrived at with case fans is that anything more then 2 or 3 fans has very little effect on temperatures. 1 intake in the front, 1 exhaust in the back, and maybe 1 more intake/exhaust will most likely get you either the coolest temperatures, or a few degrees away from the coolest temperatures you can achieve using a non-watercooled setup. I think the heatsinks and fans attached to the heat generating components perform almost all of those components cooling and that as long as there is enough air and open vents for the heat to escape to, with perhaps 1 exhaust fan to help pull it along, then all those extra case fans dont play that much of a roll in expelling that heat.
 
Top