Using 3pin Y adaptors to connect fans to motherboard?

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CrimsonCutie

Senior member
Jul 8, 2005
244
0
0
Originally posted by: NotoriousWES
Thanks guys, I never realy thought of that. So if I would use the Y splitters to just connect the RPM wire to the board I would be ok then?

thats the best idea.. just run the RPM nonitor wire to the mobo connections.
 

JEDIYoda

Lifer
Jul 13, 2005
33,986
3,321
126
Operandi---states--

If you have any common sense at all it is safe.

I bet you meant to say that -If he has any common sense he will not use the y connectors for his stated purpose!! The mobo connectors were never meant to run more than one fan per connector!!

Why is it that to get your point across Operandi you berate and try to badger people into believing that you are correct??
Case in point--If you have any common sense at all it is safe.

Totally uncalled for to question whether a person has common sense.

You don`t get brownie points badgering or putting people down!!
 

Operandi

Diamond Member
Oct 9, 1999
5,508
0
0
Originally posted by: JEDIYoda
Operandi---states--

If you have any common sense at all it is safe.

I bet you meant to say that -If he has any common sense he will not use the y connectors for his stated purpose!! The mobo connectors were never meant to run more than one fan per connector!!

Why is it that to get your point across Operandi you berate and try to badger people into believing that you are correct??
Case in point--If you have any common sense at all it is safe.

Totally uncalled for to question whether a person has common sense.

You don`t get brownie points badgering or putting people down!!

The comment wasn't directed at anyone in particular, I'm not putting anyone down. If you use some common sense (think before you do something), and use sensible fans Y-splitters are not a problem. I?m simply stating it?s no big deal, some people here seem to think the only way to run fans is off the molex connectors, which isn?t the case.

The connector wasn't designed with any particular number of fans in mind; it doesn?t matter how many fans you use as long as you pay attention to how many watts your drawing.
 

JEDIYoda

Lifer
Jul 13, 2005
33,986
3,321
126
again...we can use a common phrase......if you use common sense....

The mobo manufasturers would have added my mobo connectors for fans if they had intended you to run more than just 2 fans off the mobo....

But hey thats just me!
 

charlietee

Golden Member
Jul 27, 2001
1,280
16
81
And again I will state that I do not recommend using the fan headers on a motherboard to power any fans expcept the Northbridge and CPU fan.

And using Y-Splitters to connect "fans" to a motherboard header is just insane in my personal opinion.

If you want to slow your fans down why not just 5 or 7 volt the fans ???

Most builders will use a dedicated line to power the hard drive or hard drives and nothing else...Most will not take and run case fans and hard drives off of the same molex connector...Either with or without Y-Splitters...Do they have a reason ??? You bet.

I can give you an example of why I do not recommend using the motherboard fan headers.

Did a comparision of 120m/m fans...Panaflo versus EverCool...I put a 120m/m fan adapter on a Swiftech heatsink to put the fans under some load...I use Lian-Li T4 temperature monitor on most of my builds with one of the temp probes attached to the back of the motherboard right over the CPU socket.

I connected the EverCool to the CPU fan header and where the system normally idled at 36-C the temps just started climbing...Went to 56-C just sitting there idling before I shut the box down.

The wires on the fan were smoking hot...Almost to the point of melting and the area around the fan header on the motherboard was extremely hot also...Not good in my book.

Took and connected the fan to a molex connector with the RPM sensor attached to the CPU fan header and the temps were stable.

Now chances are that just the traces to the fan header would have gotten cooked...But no telling what else is in running right there beside the fan traces...Might just loose the fan header...Maybe not...Just loosing the fan header is a reciept for distater in my book...Much less what other traces might get burned in the process.

More importantly is if you are just trying to control the noise of your box the easiest and cheapest (free) is to just 5 or 7 volt the fans...I do not use fan controllers because I have never encountered a fan that could not be tamed using this method and a bad experience with a Digital Doc 5...Of course I do not do the Tornado, Delta thing so on those fans that are know to be extremely loud I have no experience and do not want any either.

Do what you want...But again my recommedation is to not use the fan headers on your motherboard for anything but your Northbridge and CPU fan...PERIOD !!!!

In my humble opinion of course.



 

Elcs

Diamond Member
Apr 27, 2002
6,278
6
81
Originally posted by: charlietee
Do what you want...But again my recommedation is to not use the fan headers on your motherboard for anything but your Northbridge and CPU fan...PERIOD !!!!

In my humble opinion of course.

What happens if your CPU fan is a Tornado or Delta? You'd run that off a header?

I posted in the Motherboards section about this a week or 2 ago, wanting to know if my mobo could handle the power draw from a 120mm Panaflo L1A and I was given no advice.

I have 2 running on the same channel of my Fan Controller and they have no problems. My fan controller dials all the way from 7v to 12v and Im finding it a touch noisy at 7v. I doubt they'd start up at 5v since even the 92mm didnt look too happy starting with 5v so I wanted to try and use the headers to allow the fans to start up then reduce the voltage to 5v.

Its quite risky to plug some of the higher power fans on headers but the line seems to be blurry. No-one seems sure whether what header can handle what power draw.
 

charlietee

Golden Member
Jul 27, 2001
1,280
16
81
Well the line is really not that blurry...The motherboard manufacturer usually gives a rating for the fan headers.

Just remember that heat will eventually kill just about any electrical componet out there.

You really want to heat up your motherboard powering case fans ???

And as far as 5 volting fans...Most even half way "decent" fans will easily spin up at 5 volts...And most fan buses will go down to 5 volts.

All this stuff I am spoutiing is not just my opinion...The statements I am making are from my experience...Not hear say...Or my buddy the computer whiz, seezzz...Or I read somewhere and they say.

People can build a computer using the exact same componets...But chances are that some will do a better job than others...I have over the years taken much time and effort to build the very best box that I can within my scope...Taking time to select everything down to the type screws I will use in certain applications.

A few years back it was pretty much common knowledge that powering a Delta off of your motherboard was a no-no...Manufacturers addressed the problem by upping the amps to the fan headers...But I still do not think it is a good idea...I mean if you absolutely had to do it...Okay...But that certainly is not the case.

As I have stated there are many ways to go about building a computer...And as to the original question asked about "using 3pin Y adatpers to connect fans to a motherboard"...I personally feel that it is "risky business" at the very least.

In my humble opinion of course !!!!!


 

NotoriousWES

Member
Jun 8, 2005
39
0
0
Thanks for all your insight guys. I decided not to risk it, and went out and bought some quieter and more efficient fans (and they have Red LEDs so I'm happy).

Originally posted by: charlietee

More importantly is if you are just trying to control the noise of your box the easiest and cheapest (free) is to just 5 or 7 volt the fans...

I know you can 5volt fans by switching the 5 and 12 volt leads in the molex connector, but how would you 7 volt the fan with out an adapter or an in-line resistor? Am I missing something?
 

Navid

Diamond Member
Jul 26, 2004
5,053
0
0
Originally posted by: NotoriousWES
I know you can 5volt fans by switching the 5 and 12 volt leads in the molex connector, but how would you 7 volt the fan with out an adapter or an in-line resistor? Am I missing something?

http://www.radiativenz.com/guides/fanvoltmod/index.shtml
You can find many other guides that describe this.

But, I recommend using a fan controller instead. This 7V mod can go wrong if you do not have enough load on the 5V rail or if the fan draws too much current.
The fan current flows from the 12V rail into the 5V rail. If the fan current is more than the current drawn from the 5V rail by the components in your computer, the fan current will be entering the PSU! Not every PSU can handle current flowing into its positive rail.

Please note that there are several "ifs" in the above paragraph. If all of those are true, you may have a problem. I am sure now many are going to come here and say "I did the 7V mod and I did not have any problems". You may do it and have no problems either. but, I wouldn't do it!

You can get a fan controller for $5 as I posted before. It will give you more resolution also since you can adjust the voltage in an analog way as opposed to either 12V or 7V.
 

Operandi

Diamond Member
Oct 9, 1999
5,508
0
0
Originally posted by: charlietee
And again I will state that I do not recommend using the fan headers on a motherboard to power any fans expcept the Northbridge and CPU fan.

And using Y-Splitters to connect "fans" to a motherboard header is just insane in my personal opinion.

If you want to slow your fans down why not just 5 or 7 volt the fans ???

Most builders will use a dedicated line to power the hard drive or hard drives and nothing else...Most will not take and run case fans and hard drives off of the same molex connector...Either with or without Y-Splitters...Do they have a reason ??? You bet.

I can give you an example of why I do not recommend using the motherboard fan headers.

Did a comparision of 120m/m fans...Panaflo versus EverCool...I put a 120m/m fan adapter on a Swiftech heatsink to put the fans under some load...I use Lian-Li T4 temperature monitor on most of my builds with one of the temp probes attached to the back of the motherboard right over the CPU socket.

I connected the EverCool to the CPU fan header and where the system normally idled at 36-C the temps just started climbing...Went to 56-C just sitting there idling before I shut the box down.

The wires on the fan were smoking hot...Almost to the point of melting and the area around the fan header on the motherboard was extremely hot also...Not good in my book.

Took and connected the fan to a molex connector with the RPM sensor attached to the CPU fan header and the temps were stable.

Now chances are that just the traces to the fan header would have gotten cooked...But no telling what else is in running right there beside the fan traces...Might just loose the fan header...Maybe not...Just loosing the fan header is a reciept for distater in my book...Much less what other traces might get burned in the process.

More importantly is if you are just trying to control the noise of your box the easiest and cheapest (free) is to just 5 or 7 volt the fans...I do not use fan controllers because I have never encountered a fan that could not be tamed using this method and a bad experience with a Digital Doc 5...Of course I do not do the Tornado, Delta thing so on those fans that are know to be extremely loud I have no experience and do not want any either.

Do what you want...But again my recommedation is to not use the fan headers on your motherboard for anything but your Northbridge and CPU fan...PERIOD !!!!

In my humble opinion of course.

You're making a big issue out of nothing. The number of fans you run off your MB headers is completely unimportant, whether it be 1 or 10. The only thing that matters is power draw, that?s it. And it's incredibly easy to figure out, volts x amps = watts.

Saying you should only run the northbridge and CPU fans off the fan headers is pretty short-sighted, think before you post.
 

BonzaiDuck

Lifer
Jun 30, 2004
16,784
2,115
126
Just throwing in my two-cents-worth here. I've used ASUS and Intel motherboards.

It seems fairly clear from the user's manual and specs as to how many amps can be powered by the combination of motherboard fan headers (a total 12V amperage), or conversely, the average amperage of fans distributed across those headers. If you only power one fan from the motherboard and use the remaining fan-headers exclusively for monitoring (providing the power via molex plugs from the PSU), you should be safe if you stay within the TOTAL amperage spec for the motherboard's fan headers.

There are several front-panel controllers available now which connect to the computer via USB, allowing for software speed settings and temperature control or variation for those settings.

But barring the desire to add the extra equipment, my choice is to run my CPU fan off the appropriate fan header and the remaining case fans from a manually controlled front-panel controller. My mobo provides a total fan-header power of 12V x 1.8A. I'm running a 0.8A (12V) Delta fan off the mobo CPU_FAN header, and only monitor wires are connected to the remaining headers. There has only been a slight increase in temperature measured from the mobo temp sensor -- maybe 1C increase.

At least with this configuration, I can load up Alfredo Comparetti's "SpeedFan" among my "startups" -- varying the speed of my Delta 120mm between about 2,600rpm and 3,400 rpm. The fan's top-end is 3,700, with 142 CFM air-movement, but anything over 119CFM doesn't increase the effectiveness of my ThermalRight XP-120. That also means that I'm effectively drawing less than 0.8A of current from the mobo.
 

Elcs

Diamond Member
Apr 27, 2002
6,278
6
81
Originally posted by: charlietee
Well the line is really not that blurry...The motherboard manufacturer usually gives a rating for the fan headers.

Well gee, mine doesnt. I guess its special.

Since my fans are pretty low draw, I might just try it.
 

charlietee

Golden Member
Jul 27, 2001
1,280
16
81
"You're making a big issue out of nothing. The number of fans you run off your MB headers is completely unimportant, whether it be 1 or 10. The only thing that matters is power draw, that?s it. And it's incredibly easy to figure out, volts x amps = watts.

Saying you should only run the northbridge and CPU fans off the fan headers is pretty short-sighted, think before you post. "

I am not trying to start a pissing contest here...I am stating not only my opinion but my experience.

I would appreciate it if you would not insult me by telling me to "think before you post"

If you do not like what I have to say then please retort my statements in a more civil manner...I have not crapped on your reply's so please give me the same respect.

Why dont you try a little respect.