optimal case fan config?

[polonyc2]

I thought the interior looked familiar.
I'd try it with the completely closed top and see what temps are like, but you're likely gonna need some more exhaust. I don't think that doing a full top exhaust is gonna help all that much - maybe a single top fan in the farthest back slot by the heatsink/rear exhaust fan just so you can make sure you're funneling all the hot air out that the CPU heatsink creates. However with the way that the different tops work on the newer fractal cases (guessing the Meshify S2 is similar to my Define 7 in that its a single, large piece) you might end up with some weird air circulation as it pulls in air from the top vents unless you block them somehow.
If you go full exhaust on top a lot of the air from those front intakes is just gonna go straight up and out the top without ever hitting any components.

Damn that noctua is a beefy heatsink.

that was my plan to go with just 1 exhaust on top...my issue was where to place the fan...the top panel has slots for three 140mm fans- top (front), top (middle) and top (rear)...I ruled out the top (front) but was trying to decide between the middle and rear...the middle would sit almost directly over the CPU cooler so I thought that might be best but it seems a lot of people are saying to place it in the rear spot close to the rear exhaust fan

I thought placing a top exhaust that close to the rear exhaust would create some kind of issue as far as airflow

the Noctua NH-D15 CPU cooler is a beast...my memory sticks wouldn't fit so I needed to raise the fan higher up on one of the cooling towers

 

[TheSlySyl]

that was my plan to go with just 1 exhaust on top...my issue was where to place the fan...the top panel has slots for three 140mm fans- top (front), top (middle) and top (rear)...I ruled out the top (front) but was trying to decide between the middle and rear...the middle would sit almost directly over the CPU cooler so I thought that might be best but it seems a lot of people are saying to place it in the rear spot close to the rear exhaust fan

I thought placing a top exhaust that close to the rear exhaust would create some kind of issue as far as airflow

Nah, it'll all just funnel out the same way. What you want to avoid is a gap above the rear fan and behind the top exhaust fan where air can just get trapped. However because of how open the fractal tops are, this is highly unlikely.

This is how I had things setup in my Fractal Define R5, which is similar in size to yours. (Though mine was a lot more cramped due to HDDs)

And this is my currently running interior of my Fractal Define 7 XL, which is obviously much larger and is slowly gaining RGB...

From my very non-professional or accurate thermal test of "putting a hand near the exhaust and seeing how hot the air is" the top exhausts way less hot air than the the the two rear exhausts, the fan below the GPU actually exhausts an incredible amount of heat during game loads but that's a difficult fan to get working. (Mines a 120mm slim fan that is milimeters away from not fitting.)

However when your exhaust fan up top is gonna be closer to your CPU cooler, you'll likely coerce more hot air to exhaust that way.
Also, you have better fans in your system than I do, so that will help.

 

[polonyc2]

However when your exhaust fan up top is gonna be closer to your CPU cooler, you'll likely coerce more hot air to exhaust that way.
Also, you have better fans in your system than I do, so that will help.

so you're saying it's better to place my top exhaust fan in the top (middle) slot over the CPU cooler or in the top (rear) next to my rear exhaust an?

related question: are the CPU cooler fans considered intake or exhaust and do they count towards the positive/negative air pressure of the total fans?...meaning I currently have 3 intake and 2 exhaust fans...but that's not including the CPU fans...

 

[doyll]

no, I just removed the top panel to install the motherboard etc...the top is not a solid panel, it's mesh with a filter (but I removed the filter since I wanted to use it as an exhaust)

the case is the Fractal Design Meshify S2

I would put filter back in so case airflow moves front to back with only surplus moving up and out. If there is more than just a llitle leaking out the top it will move air from in front of CPU cooler up drawing heated air coming off of GPU up in front of and then into CPU cooler.

 

[TheSlySyl]

so you're saying it's better to place my top exhaust fan in the top (middle) slot over the CPU cooler or in the top (rear) next to my rear exhaust an?

related question: is the CPU cooler fans considered intake or exhaust and do they count towards the positive/negative air pressure of the total fans?

No, you want it as close as possible to the rear exhaust fan. So they're both sucking air the same way.

The CPU cooler fans themselves aren't considered intake or exhaust as they're dealing purely with the air that's already inside the system. Intake is pulling fresh air into the case, exhaust is pushing hot air out of the case.
Same reason that GPU coolers aren't considered intake or exhaust unless they're blower style which is actively exhausting hot air outside the system.

 

[polonyc2]

looks like my plan to add a 140mm exhaust on top is not happening...when I went to install it, the CPU power plug is blocking it...so no can do...a 120mm fan will fit so I might just go that route and order a Noctua 120mm...that's why I hate this new trend of mid-tower cases...I always prefer building in full tower because of the extra space but full towers are hard to find nowadays (good ones at least)...I used to always go with Lian Li for that reason

 

[D-EJ915]

If a 120 doesn't fit in your slot cover area and are wanting to go that route you can always get a 92mm or 80mm fan, most people seem to forget they exist these days lol.