[SOLVED] ATX Mid-Tower Fan Config

[mrchristianbauer123]

I'm ordering 6 fans for my corsair carbide 275r mid-tower case (https://www.amazon.com/gp/product/B079K1W3KB/ref=ppx_yo_dt_b_asin_title_o04_s01?ie=UTF8&psc=1 ) and already have one aio liquid cpu cooler (https://www.amazon.com/gp/product/B00FZHWFEW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 ) which has two fans. Since I can mount 3 fans on the front, 2 on the top of the case, and one in the back (where the radiator is already situated), I was wondering what was the best config for all of those fans to have the best cooling potential?

 

[The prime mediocre]

What components are you cooling? I'd recommend filling the front with intake fans (either 2x140mm fans or 3x120mm fans). The fans at the top should be set to exhaust, but won't be particularly helpful unless you're shifting a lot of heat (like, a 140W CPU and two GPUs).

 

[mrchristianbauer123]

What components are you cooling? I'd recommend filling the front with intake fans (either 2x140mm fans or 3x120mm fans). The fans at the top should be set to exhaust, but won't be particularly helpful unless you're shifting a lot of heat (like, a 140W CPU and two GPUs).

I have an i7 4790k and and rtx 2070, the 2070 has been running pretty hot too, usually around 80 during gaming after only maybe 30 min

 

[The prime mediocre]

80C is perfectly normal for many 2070 cards. You'll see some improvement from adding strong intake fans.

It's hard to tell from the listing: did the case include SP120s or generic Corsair-branded fans?

 

[mrchristianbauer123]

80C is perfectly normal for many 2070 cards. You'll see some improvement from adding strong intake fans.

It's hard to tell from the listing: did the case include SP120s or generic Corsair-branded fans?

just some pretty generic fans, but generally I was wondering if I should have positive air flow or equal? because on the cpu aio cooler, it has two fans mounted onto it on the back of the case, would that really affect the air pressure much?

 

[The prime mediocre]

The stock fans just aren't very effective pulling air through the front filter. I'd recommend positive pressure, because it gives you the best airflow per fan added. Replacing the stock case fans with two PWM (4-pin) ~1800RPM fans with high static pressure will dramatically increase the amount of cool air coming into your case. It'll be quieter and cleaner.

The two fans on the AIO (a "push-pull" config) are really all about getting as much air through the radiator as possible. It's not more effective at exhausting heat than any other 120mm exhaust fan.

 

[mrchristianbauer123]

The stock fans just aren't very effective pulling air through the front filter. I'd recommend positive pressure, because it gives you the best airflow per fan added. Replacing the stock case fans with two PWM (4-pin) ~1800RPM fans with high static pressure will dramatically increase the amount of cool air coming into your case. It'll be quieter and cleaner.

The two fans on the AIO (a "push-pull" config) are really all about getting as much air through the radiator as possible. It's not more effective at exhausting heat than any other 120mm exhaust fan.

I already have the 6 fans shipped, so I guess I'll be adding them either way, should the front 3 fans all be intake? but what of the other 3 on the top? if they're all exhaust then it won't be positive air pressure right?

 

[The prime mediocre]

The front three should all be set to intake. The 275R only has space for two 120mm fans at the top. If you install three front intakes and two top exhausts, you'll have roughly neutral airflow. Setting the fans to run at different speeds will let you switch between positive and negative pressure at will (e.g., setting the front fans to 1200RPM and the top fans to 800RPM for positive pressure).

What fans are you using?

 

[Karadjgne]

Pressure shifts. You can't just say 3x intakes and 3x exhaust = neutral, or 2x exhausts = positive, doesn't work that way.

When a blade moves through air, it creates a low pressure area behind it, which is added to the next blade, rinse and repeat. The faster the blade moves, the lower the pressure area until you get a decent sized area in front of the fan. Nature abhors a vacuum of any sort, so air will move to fill the void. The lower the pressure, the more air that will move. And that whole block of air is supported by the front intakes. However, air isn't picky, it'll move from the nearest available space, which is commonly the pci slots by the gpu or an open top fan vent, less so the case air. A positive pressure system is one that negates the draw from next to the exhaust fan, no air from outside unfiltered. A negative system pulls air from anywhere and everywhere.

At low rpms, there's not much vacuum on the exhaust, so is quite easy to get a positive system. Under heavy loads and high fan rpm, this can shift to negative, there's enough draw from the fan to overcome the intake pressure, and start sucking outside air. Part of the reason the Meshify C is so highly rated for airflow is 3x intakes and 1x exhaust make it near impossible to get a negative flow at any rpm, as long as the top vents are sealed.

 

[mrchristianbauer123]

The front three should all be set to intake. The 275R only has space for two 120mm fans at the top. If you install three front intakes and two top exhausts, you'll have roughly neutral airflow. Setting the fans to run at different speeds will let you switch between positive and negative pressure at will (e.g., setting the front fans to 1200RPM and the top fans to 800RPM for positive pressure).

What fans are you using?

these (https://www.amazon.com/gp/product/B07KGZ89V5/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 )

 

[mrchristianbauer123]

Pressure shifts. You can't just say 3x intakes and 3x exhaust = neutral, or 2x exhausts = positive, doesn't work that way.

When a blade moves through air, it creates a low pressure area behind it, which is added to the next blade, rinse and repeat. The faster the blade moves, the lower the pressure area until you get a decent sized area in front of the fan. Nature abhors a vacuum of any sort, so air will move to fill the void. The lower the pressure, the more air that will move. And that whole block of air is supported by the front intakes. However, air isn't picky, it'll move from the nearest available space, which is commonly the pci slots by the gpu or an open top fan vent, less so the case air. A positive pressure system is one that negates the draw from next to the exhaust fan, no air from outside unfiltered. A negative system pulls air from anywhere and everywhere.

At low rpms, there's not much vacuum on the exhaust, so is quite easy to get a positive system. Under heavy loads and high fan rpm, this can shift to negative, there's enough draw from the fan to overcome the intake pressure, and start sucking outside air. Part of the reason the Meshify C is so highly rated for airflow is 3x intakes and 1x exhaust make it near impossible to get a negative flow at any rpm, as long as the top vents are sealed.

what would be best for a case like mine then?

 

[The prime mediocre]

Your 275R is very similar to the Fractal Meshify that Karadjne mentioned, except that the top vents are open. Like I mentioned above, you'll get solid results with three intake fans. You've got an 88W CPU (assuming it's overclocked) and a 175W GPU, so the gains from adding even more fans will be minimal.

 

[Karadjgne]

Honestly, I'd have gone for 2x 140mm Noctua A-14 ippc 2000 rpm in front, and moved the stock fans to top exhaust. I'd also set fan curves to keep the rpm low-moderate for the exhausts, leave the aio fan controlled by cpu and run the A-14's higher. That'll keep the aio from sucking air from the top vents, improve gpu exhaust characteristics and apply maximum air to the aio.