Low RPM with Cooler Master Megaflow 200mm

[Fliggle_Slaps]

Hi Guys, I recently got myself a Megaflow 200 and got it installed in my Corsair 600T case but found it's not running as fast as it should. I've tried plugging it into 2 different chassis fan ports on the motherboard, tried setting it to Turbo in the BIOS and finally plugged it direct to the PSU. No matter what it runs at around 450rpm.

Do you guys think it's faulty or could I have done something wrong with the installation perhaps? Would something like tightening the screws too hard affect this?

 

[Deuce65]

Why don't you describe *exactly* how you have it connected, and where you see it running at 450?

 

[Fliggle_Slaps]

I've got it mounted on the front of a Corsair 600T, the power cable going into this and plugged into the PSU.

The readings that showed the rpm were in the Sabertooth Z77's UEFI BIOS, in the SpeedFan app, and in the Asus AI Suite II (which I know people dislike and recommend uninstalling). All 3 showed the rpm at around 450 and I couldn't force the fan to run any faster using any of these tools.

 

[Deuce65]

Okay so using the adapter like you mentioned means that it is getting power directly from the PSU, and is not connected to a fan header and so can't be reporting it's speed to the MB. So whatever speed you see there is wrong; the MB actually has no idea what speed it is running at or if it is even running at all.

 

[Fliggle_Slaps]

Like I said in the first post, I originally tried plugging it into the MOBO. I tried 2 different CHA_FAN ports and they both, just like plugging into the PSU, run at a bad speed.
After plugging it into the PSU, I can still tell by looking at it that it's not full speed.

 

[Deuce65]

Right and I understand that but when you plugged it into the fan header it is then running under speed control so of course it isn't running at full speed. Thats the whole point of speed control. Picking turbo as you did doesn't change that because if the PC isn't warm, it won't run at full speed unless you set it to anything but full speed.
As for your visual check, the fan has a top speed of 700RPM. There is simply no way you can visually tell the difference between 450RPM and 700RPM.
Why don't you do this. Put it on a fan header. Turn off speedfan. Run the ASUS fanxpert fan tuning software. As part of the process it will turn off everything but that one fan and will report it's full speed.

 

[Fliggle_Slaps]

In the BIOS, all fans are set to run at a minimum 600rpm. Am I misunderstanding what that function does, or is that a sign the fan is not functioning properly?

When I was looking at the fan to judge if it's faster, it's not the fan itself I'm looking at, rather the sticker in the middle which is more visible than it should be. I don't think I should see it this clearly if it were running at full speed.

From what I can tell, AI Suite III should not be used on the Sabertooth Z77. Since Fan Xpert only comes with AI Suite III it seems I won't be able to get it.

I had tried to set the fan speed to 100% using SpeedFan and AI Suite II, don't they force it the same way Fan Xpert would?

 

[Deuce65]

It should be setting as a percentage, not a specific RPM, because the BIOS has no way of knowing what fan you have. Set it to 100 percent and see what happens. Or full speed, whatever they have it labeled as.
Regarding the label, you should be able to see it clearly. You should not be able to read it though, but you shouldn't be able to read it at 450 either. Is the LED on?
I don't know about fanspeed; sometimes it works, sometimes it doesn't, and it has to be setup just right to do anything. So that would not be the best software to test it with.

 

[Fliggle_Slaps]

Unfortunately in the BIOS it only gives 3 options for each fan:
- Chassis Q-Fan Control [Enable/Disable]
- Chassis Fan Speed Low Limit [Various RPM speeds]
- Chassis Fan Profile [Standard, Turbo etc]

However in SpeedFan and AI Suite I did set those to 100% no matter the temperature readings but the fan didn't go any faster.

The LED is on and seems pretty bright, so I'd guess it's getting enough power.

It was also the first time I've used SpeedFan, or even heard of it, so I'm not all that confident I did it right. Basically I made an advanced fan control and set it to go at 100% if the temp is 0c or more. I pretty much did the same thing in AI Suite II aswell, except if the temp is 30c or over (since I couldn't choose a lower temp).

 

[Deuce65]

Well ignoring the speedfan for the moment cause as I said, it is really picky.
I really think your fan is running fine. Thing is the fan is very low speed, it maxes out at 700 which if you are used to normal speed, 120mm fans, looks REALLY slow. Second, if the LED is on and at all bright, it is getting enough voltage that it should be running at least 600 or so RPMs. I suppose it is *possible* it has a bad motor and is getting the full voltage but not running at the full speed, but based on what you are saying I really think it is running correctly.
Maybe get something like CPUIDs HW monitor (free) and see what that says your fan speed is?

 

[Fliggle_Slaps]

I'm starting to think maybe it is that slow on purpose as you said. I'll have a look when I do something intensive soon to see if it speeds up when the temps go up.

But before that, do you know how to make fan speeds appear in HWMonitor? All I see is this.

 

[Deuce65]

They should just appear. It may be your MB it doesn't like. Try restarting though sometimes when you have multiple monitoring softwares running it doesnt read right.

 

[Fliggle_Slaps]

OK so I've changed the config for the fans a bit. Front Megaflow 200 is on the MOBO (CHA_FAN 1), two top exhaust fans are on the MOBO (CHA_FAN 2/3) and my rear exhaust is to the PSU.

You were right Deuce, the fan was going slow because it didn't need to be going fast. After switching it back to the MOBO from the PSU, the readings changed to 530~rpm. That was already a nice boost from 450, but I thought I'd try to set the fan curve to always be 100% again. This time it worked...so the Megaflow 200 is now going at a constant 730~rpm. (also you were right about conflicting software, HWMonitor worked after closing AI Suite II.)

Honestly the reason I was worried in the first place was because AI Suite II was showing the RPM reading in yellow instead of blue. This made me think it was a fault or error. Now that it's full speed, the reading is in blue like the rest.

Thanks for your help and support Deuce, I've learned now to judge on what really matters. In this case, the temps that the RPM readings rely on.

 

[Deuce65]

Glad I could help. I have two haf XBs with those fans and I don't even use the speed control, the fan is so quiet at full speed I just use the little molex adapter and let it run at full speed and never hear a thing. I kind of expected it to be a garbage fan but it actually is pretty good.

 

[Fliggle_Slaps]

I'm pretty happy with it all around. It's a great blue LED that I was aiming for, quiet and moves a decent amount of air. I just wish the 600t case didn't make it difficult to install...
Unless you move the hard drive bays, you can only fit a 200x200x20 so I had some "fun" moving my hard drives and getting them connected at the bottom of the case where cables don't have room to bend. Even worse is I had to sacrifice a HDD because the bay only holds 3, so it won't be coming back until I decide to drill holes on top of the bay to attach my SSD on top.