Fractal Design Define R5 FAN ORIENTATION ???

[jcsn]

in terms of static pressure fans, do 120mm or 140mm ones do a better job ? airflow/cfm/noise level comparison ??

specs:

fractal design define r5 case
gtx 970 g1 gaming
intel i5 4690k
coolermaster v650 80+ gold

would the radiator with 2 x 140mm fans at the top be enough for exhaust ? I am planning to use more intake than exhaust or keep them even.

So if I change the rear fan to intake, I will have:



radiator at the top 2x140mm (exhaust)



rear 1x 120mm (intake) AND BUY A 120MM DUST FILTER



bottom 1x140mm (intake)


front would be SP or AF preferably ?? and 2x120mm or 2x140mm please ??





OR the other alternative would be :





radiator at the top 2x140mm (exhaust)



rear 140mm (exhaust)



bottom 140mm (intake)



front 2x120mm VS. 2x140mm ?? AF vs SP ?? (intake)





4 intake and 2 exhaust OR 3 intake and 3 exhaust ?





SPECS


Cooling system
•Front: 2 – 120/140 mm fans (included is 1 Fractal Design Dynamic GP14 fan, 1000 RPM speed)
•Rear: 1 – 120/140 mm fan (included is 1 Fractal Design Dynamic GP14 fan, 1000 RPM speed)
•Top: 3 - 120/140 mm fan (not included)
•Bottom: 2 – 120/140 mm fan (not included)
•Side: 1 – 120/140 mm fan (not included)
•Fan controller: 3 step fan controller for up to 3 fans
•Dust filters: Bottom and front intakes

Water cooling compatibility
•Front – 360, 280, 240, 140 and 120 mm radiators of all thicknesses (requires removal of drive bays)
•Top – 420, 360, 280, 240, 140 and 120 mm radiators. (A thickness limitation of 55mm for both radiator + fan applies on 420, 280 and 140 mm radiators) (420 and 360 mm radiators require removal of the ODD bay)
•Bottom – 120 or 240 mm radiator (Use of radiators in the bottom position limits the PSU length to 165 mm)
•Rear – 120 or 140 mm radiator

 

[Bannereus]

I'm pretty sure that fan characteristics (airflow, pressure, noise) depend more on the make and purpose of the fan, rather than the size, and so it will vary fan by fan, so do your research or look for a fan expert (not me 😛)

My instinct is to go with the three 140mm intakes (front x2, bottom x1 if you need the HDD cage) to take advantage of the included dust covers, and three 140mm exhausts (top x2 above rad, 1x rear at low speed)

Using the included fan controller, run the intakes at a higher speed than the total exhaust, (run the rear exhaust on low, because the top fans will respond to cpu temp I'm assuming) such that you maintain positive pressure

To address your idea of the rear intake: first, the vent is sized for 140mm, so regardless of intake fan size, you need something to cover it completely (>= 140mm); also, with sufficiently performing fans on the radiator, cooling performance won't suffer from the lack of an extra intake

With that processor and top radiator, your graphics will be putting the most heat into the case, and there is a passive honeycomb grill on the rear panel to let some of it out (as long as there is positive pressure), but the rear exhaust is needed to take out more of the heat that rises in the case before it gets to your radiator exhaust


Using the two included fans for intakes is pretty safe, and two purpose-designed fans for the radiator; your choices for the remaining intake and rear exhaust may tip the balance in terms of airflow (research your fans if you are concerned at that level)
Also, if you can ditch the HDD cage, you could consider front or bottom mounts for your radiator, but that's a whole new kettle or fish