ml140 pro fan rotation question

I understand the ML140 fan rgb leds will show from either side of the fan. I am building a new rig and placing two ML140 pro's on the bottom of the crystal 680 case. I want the fans to push the air upward into the case but also want the nice looking Corsair logo side of the fan facing up into the case. This logo side up fan position unfortunately right now pulls the air out of the bottom of the case. Don't want that. Can the fan be either wired backwards somehow or be rotation reversed in the icue software to make these two bottom fans turn opposite their normal rotation? The ideal situation for me is to have the Corsair logo viewable looking thru the glass door while pulling the cool air into the case.

No, that's not possible.

That's a bummer since I ran into similar problems. I'm currently tinkering on a corsair white build and wanted to replace all the stock fans of my 680x with white LL120s RGB fans since those seem to be the only ones available in an entirely white design. Now I checked (yeah should have done that earlier) that only the intake side is lit so that kinda ruined my idea of the bottom fans sucking fresh air in. In the end I now have 3 front fans as intake and 5 fans as exhaust (2x top, 1x rear, 2x bottom). Would be great if I simply could change the flow direction of the fans on the bottom.

It's not as simple as just reversing the fan blades. Look at the blades. See how they are "scooped"? They will efficiently move air on only one direction. Reversible blades would either have to be straight (reducing their efficiency) or have some kind of way to reconfigured themselves.

 

The new QLs are pretty from both sides. But also more expensive. And not available in white.

 

And ... having more exhaust than intake will increase dust buildup inside the system due to negative pressure. You can manage this by being super-careful with the fan speeds but it'd be a tough battle. Not sure if that's an issue for you but I have 3 dogs and 2 cats ... so it'd be a massive issue for me.

It's not as simple as just reversing the fan blades. Look at the blades. See how they are "scooped"? They will efficiently move air on only one direction. Reversible blades would either have to be straight (reducing their efficiency) or have some kind of way to reconfigured themselves.

 

The new QLs are pretty from both sides. But also more expensive. And not available in white.

 

And ... having more exhaust than intake will increase dust buildup inside the system due to negative pressure. You can manage this by being super-careful with the fan speeds but it'd be a tough battle. Not sure if that's an issue for you but I have 3 dogs and 2 cats ... so it'd be a massive issue for me.

 

Well I indeed have 2 cats but they are not allowed in my room where my pc is so that's not really an issue, moreover the 680x comes with several dust filters so guess that's not going to hurt that much. But nonetheless it is not "optimal" having negative pressure in the case so it will bother me for sure :)

 

I could try to adapt the speed controls for the intakes and exhausts individually to create a slightly positive pressure but I don't think I'll be able to do the right math (regarding the radiators, positioning of the case, etc) to get that somehow equal.

The issue with negative pressure is that you'll get air coming in from the cracks, crevices and other vents that don't have filters.

You want all of your intake to be through the filters.

 

As for the cats ... how do you get them to respect not being "allowed" in a room? My dogs will usually respect that but the cats really just don't care what I say.

You do have a 680x case and those two bottom fans are two more than most standard cases with the same front in, top/rear out design. If you set the bottom fans to the minimum speed, they won't have much effect on the overall flow while still providing the desired lighting. The 680 design is closed at the door, so the only place air is coming in is through the filtered front. A slight bias to negative pressure will not have much effect. Your environment is either PC hazardous or its not. A PC in a room full of cats will collect hair, no matter the fan arrangement. My current O11 build is all negative pressure without a single intake fan. It is one of the cleanest I have ever made. Environment trumps fan layout and I don't think it matters anyway for this case. Besides, you can always adjust intake/exhaust balance through fan speed control. The days of having to buy the exact fan speed you need and run at 12v are long gone.

 

If there is some reason you need increased airflow in the bottom the of the case, then you will have a decision to make.

Hi and thank you both for your answers. The door to my room is always closed so there is no issue with animals or whatever. The pc itself stands on my gaming table (ultradesk xxl) so I guess I can safely say that it's not PC hazardous :) Both CPU and GPU are watercooled and the airflow is mainly to cool the rads (240mm at the top and 360mm at the front) so the idea to keep the bottom fans at low rpm is quite good.

As for the cats ... how do you get them to respect not being "allowed" in a room? My dogs will usually respect that but the cats really just don't care what I say.

 

The difference between dogs and cats:

- Dogs will come when you call them

- Cats will take a message and get back to you

- Cats will take a message and get back to you

 

Maybe. And only when the food bowl is empty.