New Build - Fans Spinning Too Fast?

WesM82

Prominent
Jun 29, 2017
11
0
520
Hi. This is my first post here and I'm completely new to building computers. I will first explain where I'm starting from for those who care to listen. Sorry in advance for the length.

A while back I bought a gaming pc, not because I'm a gamer (I actually don't game at all) but I was tired of seeing all the videos I watch constantly buffering and not being able to watch in at least full hd if not higher. I had a lot of general problems with my previous computers with cheap parts so I wanted something a little more sophisticated, less troublesome and more future proof.

Anyway, I picked up this custom comp very cheap from a guy who was kicked out of his place and was forced to sell his whole gaming setup in a hurry. It came with a GTX 1070, Asus M5A97, FX-8350, Corsair Ram, Seagate hdd, and Samung ssd. I used it as is for a while but one of the fans wasn't hooked it up, the front case fans were missing, and the case was very ugly to my eyes. I decided I would buy a new case, modular psu and quality fans and keep the rest.

So specs of the build are:

NZXT S340 Elite Matte Black
Asus M5A97 LE R2.0 Motherboard
AMD FX-8350 CPU w/ stock copper pipe air cooler
Corsair Vengeance 8GB
EVGA GTX 1070 Founders
EVGA Supernova 550 G2
Seagate 250GB HDD
Samsung 850 Evo 250GB SSD
Corsair ML140 Pro Fan x 2 up front

I took my time building it and it seems to have turned out very nicely. It turns on and loads to the desktop without a hitch.

PROBLEM: The problem now is that the two front fans are spinning at a very high rpm around 2800 or so and because of this they are very loud. I triple checked my connections. I have the two front fans connected to a rosewill 2 into 1 splitter plugged into the chassis 3 spot on the motherboard, while the rear and top fans (stock nzxt 120mm) are connected to a splitter plugged into the chassis 2 spot. I went into bios but was unable to change fan speed. I don't know if that's even possible though. I did some research and others have had this same problem on this motherboard. The fixes they gave didn't quite make sense to me though or I need clarification.

What are my options short of getting a new motherboard?

ps..I'm not currently using the computer as I know the fans spinning at that speed are well above their intended 1600rpm max. I only had it on for short periods to attempt to figure out the issue in bios but quickly realized I wasn't getting anywhere.
 
Solution
I've seen different answers regarding splitting the cpu header. I'm going to leave it as is for now. The temp is showing 32 degrees and I'm not gaming so not doing anything to push the cpu to get hot.

I'm not sure why, but the computer is booted up fully and working now. I think this Samsung ue590 monitor has issues with detecting a signal. It's not the first time I've had problems with it. I've restarted the computer a few times now and no issues since.

Thanks
From a bit of searching around, it does look like other people have had similar fan header problems with that motherboard.

Personally, I would just re-wire the fan cables so that they're plugged into a fixed 5v molex power connector, something like what's shown in this example...

https://www.techpowerup.com/articles/other/137

Just be careful that you're connecting the right cables to the right places. Otherwise, get a fan-controller, which have little knobs that you can turn to manually turn downthe voltage going into your case fans.
 


Thanks you both for the fan controller suggestion. I had looked into that but just wasn't willing to put down more $$ unless I absolutely needed to. Will the fan controller override whatever fan speed setting/voltage that the fan headers output? This is all new to me so it's a little confusing.
 
I am sorry what I said about the fans did not mean anything by it / as for the fan controllers I think they do a good job I was looking into it a long while ago before I bought my watercooling because I hated fan noise and my H110 does a great job of cooling the cpu and I dont need any fans except the ones on the cooler there so big I do not hear them.
 
This should work without customizing or third-party fan controllers, IF it is used correctly. So let's review the essentials.

The mobo has three CHA_FAN headers, and the manual indicates that they are of the 4-pin type and use only PWM Mode for control. That MAY not be correct - many ASUS mobos allow either PWM or DC Mode on their CHA_FAN headers, but your manual does not mention that. This detail is important because PWM mode CAN control the speeds of ONLY 4-pin fans. It cannot control the speed of 3-pin fans. A 3-pin fan plugged into a header that uses PWM Mode will run full speed all the time.

HOWEVER, that does not match what you describe. You say, "the rear and top fans (stock nzxt 120mm) are connected to a splitter plugged into the chassis 2 spot". Now, the fans pre-installed in those positions of that case are 3-pin fans. So IF the CHA_FAN2 header is using PWM Mode, THOSE two fans are the ones that I would expect to be running full speed. Yet you say they are not. So, check to be sure about them. How? Well, careful observation when you start up AFTER the system has cooled down. You need to have the case open so you can observe those fans during the first few seconds of the start-up process. The "normal" start-up sequence for any fan connected to a mobo header is this. Right at start-up the fan goes to full speed immediately. After a few seconds as the POST process proceeds, the system gets actual temperature readings and starts its normal control of the fan speeds. For a cool system, this means that the fans slow down, and will speed up later when the system heats up from use. SO, are those pre-installed rear and top fans really starting fast then slowing down very soon? If they are, then they must be getting the proper DC Mode control signals from the CHA_FAN2 header, even though the mobo manual does not indicate that this is possible.

On the other hand, if those two fans never slow down, are THEY the ones making the noise you notice? If not - if whatever noise they make is tolerable - we'll ignore them for now and go on to the new fans.

Now, those Corsair ML140 PRO fans that you installed in the front are of the 4-pin type. That means that, whether or not your CHA_FAN3 header they are attached to is using PWM Mode, they really should be under mobo speed control. So, repeat that test of what the fans do at start-up, concentrating on those ML front fans. Do they really start up full speed and stay that way, or do they slow down?

Next thing to check it that Splitter from Rosewill they are connected through. For the control system to work, the Splitter MUST be of the 4-pin type. That is, the female connector on it that plugs into the CHA_FAN3 header must have 4 holes, and its two male output connectors must be designed with 4 pins. EXCEPT, one of the two output arms should be missing Pin #3. That, too, is important. A mobo header can only deal with a speed signal coming in from a fan on Pin #3 from ONE fan. Some earlier Splitters were made incorrectly with full wires and pins for all four wires to both fans, and this feeds to the mobo TWO fan speed signals, causing great variability and confusion in displaying the speed of the fans on that header. So, check both factors. That Splitter should NOT feed signals from Pin #3 of BOTH fans back to the mobo header. If your Splitter is of the faulty older design, that could account for the very high readings you seem to get. And the Splitter SHOULD have 4 wires (not 3) for the four connections pins, excepting something missing for Pin #3 of ONE fan.

IF the Splitter used for the ML140 fans is of the 3-pin system, it will not be allowing the PWM control signal from Header Pin #4 to get to the fans, and they will not be under mobo speed control.

Lastly, check the configuration of the CHA_FAN headers in BIOS Setup - see the manual on p. 3-24. In particular, look how "Chassis Fan Profile" is set for each header separately. They all should be on "Standard" to allow the mobo to control the fans.

So, check those items and report back here what you find.
1. Which fans really are altering their speed in responce to mobo signals (if any), and which only run full speed all the time?
2. What are the details of the Splitter used for those two front ML140 fans?
3. Have you verified that all the CHA_FAN headers are set to "Standard" control profile?
 
I very much appreciate your lengthy response. I've been very busy with work lately and haven't gotten a chance to mess with the computer. I plan to do so tomorrow. I will update then. Thanks
 
Hi again. I've finally found some time (or just stopped being lazy) to check a few of these items.

First off, when powering the computer on all fans are moving slow (or normal?) for a few seconds and the sound level is very tolerable. The top and rear fans don't seem to speed up at all even after computer is fully up and running. I put my ear to them with the case opened. However the two front fans definitely speed up a great deal after those first few seconds and are the cause of the large increase in sound. Also, the CPU fan while not quiet, is not the cause of the noise.

As to the splitters, I checked the pins/wires on both headers and all 4 fans. All have 4 wires and 4 pins. So perhaps Amazon shipped me the old style splitters? Could I remove one of the pins myself?

I'm having trouble getting into BIOS now. Initially I was able to get into it pushing delete or f12 (cant remember). But now even if I push it down right after pushing power button it goes straight to desktop.
 
Thanks for that info.

So, clearly it is the front fans that run very fast and cause the noise. They are connected to the mobo CHA_FAN3 header via a Splitter with 4 pins on all connectors. We need to check the splitter's internal connections and the configuration of the header in BIOS Setup.

First, the fact that both the Splitter's output connectors have all 4 pins may or may not be a problem. There are two ways that a Splitter can limit itself to sending back only one fan's speed signal. One way is not to have a Pin #3 in one of the two output arms; apparently your Splitter is not designed this way. The other way is simply not to have a wire from the female input connector of the splitter to Pin #3 of one of the two male output arms. So, examine the wires carefully and see if a wire is missing on one arm. As confirmation, use a continuity checker (a resistance meter or whatever) to verify the connections from the female to each of the two male output connectors of that splitter. (Contacting a hole in the female connector can be tricky - try inserting a small sewing pin into the hole.) Pins 1 on each connector should all be connected to each other. Likewise for Pins 2 and Pins 4. Pin 3 from the female should be connected to Pin #3 of ONE output male only, and NOT to the other male. If you find that BOTH male output connectors have connections for Pin #3 back to the female input connector, it is one of the faulty designs. To fix that, removing the pin on one output may work, but may be difficult. It may be easier simply to take wire cutters and snip the wire to Pin #3 on ONE output connector. Then just tape it up so it does not short out by error later.

Now verify one further bit on that splitter. Ensure that there is a good connection from Pin #4 on the female to Pin #4 of each male output. These are the signal lines for the PWM signal. If the fan does not receive that signal, it will run full speed.

Now, getting into BIOS Setup. The manual says just push the "Del" key during POST. What I find is that sometimes the system is busy doing POST things and does not happen to notice when you push that key. Instead, as soon as I push the power-on button, I hold down the "Del" key until the POST finishes and the system does enter BIOS Setup and show you its opening screen.

If it opens in EZ Mode (p. 3-3), use the F7 key to switch to Advanced Mode (p. 3-4). There click on the Monitor tab at top. See p. 3-22. Scroll to the bottom of the list to reach Chassis Q-Fan Control, p. 3-24. Go particularly to the CHA_FAN3 header. It should be Enabled. Check the Chassis Fan Profile - it should be "Standard", and definitely not Turbo. As long as it is not in Manual Profile, the custom settings are not applied. While there, check for something else that I do NOT see in the manual. SOME mobos allow you to select which built-in temperature sensor is used to guide each fan header. IF you find that option for the CHA_FAN headers, make sure each is set to use a sensor on the mobo, and not the sensor inside the CPU chip. If you make any changes in here, be sure to SAVE and EXIT to save your new settings and reboot.

After all that's done, let us know what results - did anything change? By the way, another thought. How do you know the front fans' speeds are in the range 2800? The fan specs say its max is only 2000. Now, if that splitter is of the faulty design and you have fixed that, this problem will have been resolved. But if you are still seeing 2800 rpm. using what tool? There are some third-party utilities that give faulty readings. The handiest tool for you to use is a utility (called AI Suite II) included on a CD that came with the mobo. If you have that CD, see the manual p. 4-1 to 4-3. AI Suite II runs as an app under Windows so you can use it to check your system and make adjustments during normal work, not just in BIOS Setup. If you don't have that CD, check the ASUS website and find that utility. If there are choices, make sure to get the one for your particular mobo.
 
Once again thanks for your informative and helpful response. I was able to get into BIOS on the second try using your instructions.

I will try and test continuity of the wires as instructed. I may try to cut the single wire as you suggested. I will let you know the results of both as soon as I can.

I set some of the settings in BIOS that I was able to. A few of them did not apply or I'm too tired right now to notice them. I will check again tomorrow when I'm wide awake.

Regarding the front fans speed, I was able to see their rpm in the UEFI BIOS Utility Page - EZ Mode. I downloaded the AI Suite II utility but I'm unsure how to extract the program. I attempted to extract all files but then couldn't find where the program was. I always get confused with that stuff.

On a slightly unrelated note, I changed the cpu to cool n quiet mode on a suggestion from another thread. It went from mid 4k rpms and annoyingly noisy to high 2's range and much more tolerable. I still think I will get a Cryorig H7 or similar if that will help to lower noise even more.

Thanks
 
Hello. I did some messing around with the computer today.

First, I plugged one of the front fans directly into the CHA_FAN3 header to test what it did. It seems to be running at a modest speed of 1300 rpm or so (if memory serves). It's fairly quiet. I still have the case sides off so noise will be lower once I get them installed. And that stock cpu cooler is not doing me any favors.

I also attempted to test continuity or the wires of the splitter but found it very tricky to keep the multimeter pins touching each end and even when I did I either got no reading or a reading that kept jumping around. The female connector on the splitter has a " 1 " on the black wire. So, does that make the red 2, orange 3 and white 4? Sorry for the dumb question. Still learning here.

Thanks
 
Ok. I tested continuity properly this time. One side of the splitter I got readings on all four pins. The other side of the splitter none of the pins gave me any reading.
 
Wow! With a continuity tester, Pin #1 on every connector should be connected to Pin #1 on BOTH of the others - that is, all three Pin #1's are connected together. Same for Pins #2 and 4. Pin #3 is the ONLY one that should not be connected on ONE of the two male output connectors. In fact, in many models one of those output males simply is missing Pin #3. So, if one of your male output connectors has NO connection of ANY of its pins to the rest of the Splitter, then the fan plugged into that one should do NOTHING. Is that right?
 
Hi. A while back I purchased a Cryorig H7 cpu cooler. I ended up damaging the stock cpu pins when removing because the cpu was basically welded to the cooler. When I tried to remove it I was carefully easing it out but still managed to exert enough downward pressure that a bunch of pins bent. I tried to straighten per instructions online using a credit card and pick. I had no luck. The pins were too damaged to repair and one ended up breaking. Even as much as I didn't want to spend more $$, I ended up buying a new 8350 cpu. I finally found some time this morning to install it and the cooler and it didn't go particularly smoothly however it is installed now. I found it pretty difficult to get the crossbars to align with the screws and it took multiple tries removing and reinstalling. Anyway, now that it's all up and running the computer wont post. I believe I may know why and already dreading having to make yet another purchase. This steal of a computer that I was going to add a nice case and a few other things to is quickly becoming a money pit.

Anyway, I noticed before I installed the cpu that the motherboard female pins had one that appeared to be missing or damaged in some way. When I moved the metal 'lock bar' all of the copper/brass pins would shine in the light however this particular one was dark. I could still see half of it from the right angle but I think it's compromised. How likely is it that this is the case? I guess another motherboard is in order..
 
Also, to try and solve my fan dilemma, I bought a 4 into 1 fan splitter. I plugged the two front fans, cpu fan, and top fan into it and plugged into the cpu socket. The rear fan I plugged into chassis fan 4 header. The computer seems to be quieter now but until its up and running a while I won't know for certain.
 
I've seen different answers regarding splitting the cpu header. I'm going to leave it as is for now. The temp is showing 32 degrees and I'm not gaming so not doing anything to push the cpu to get hot.

I'm not sure why, but the computer is booted up fully and working now. I think this Samsung ue590 monitor has issues with detecting a signal. It's not the first time I've had problems with it. I've restarted the computer a few times now and no issues since.

Thanks
 
Solution