PWM Splitter problems!

[blu4]

Hi,

I usually resolve my problems via google and other forums however, this problem is VERY odd. I have got a PWM splitter:



The problem is: Whenever I plug in 3 fans (all fans are PWM- i have 4 alltogether) the splitter and software runs perfect- i am able to set speeds and so on. When i plug in the 4th fan- the software goes to sh**s and all fans start going 100% full blast.

tl;dr

3 fans= PWM controls work
4 fans= PWM doesn't work and all funs run at 100%

 

[Automata]

Blu4, PWM is not something I know a lot about, but it sounds like the fan header you are using isn't able to drive all four fans from one connection.

 

[RnRollie]

That's weird.. does it matter which fan goes where?
I mean, have you tried the 4th fan into one of the other plugs.
It's to determine if its the fan causing it, or if there is an issue with the cable/plug itself.

If the problem "moves" with the fan, then its the fan. If it happens when you plug a fan in the "last" port, then its the cable

Following possibilities:
1. a short in the cable
2. the cable does reports TWO RPM signals
3. somewhere a pin is swiched (note this can be a switched pin/wire on the fan also)

Which fans are you using? Make/Model.

And this is a stupid question.. the cable IS getting power from the PSU through the molex? You're not using just as a fan splitter?

Note: this is an AKASA cable i assume?

 

[ATMINSIDE]

Sounds like you're exceeding the limit of the PWM signal pin on the motherboard.

Look at a splitter like the Swiftech PWM Splitter as it actually boosts the signal so that the motherboard sees it as one fan instead of having four fans drawing the signal.
Hope that last bit made sense.

 

[RnRollie]

Sounds like you're exceeding the limit of the PWM signal pin on the motherboard.

Look at a splitter like the Swiftech PWM Splitter as it actually boosts the signal so that the motherboard sees it as one fan instead of having four fans drawing the signal.
Hope that last bit made sense.

hmmm
without going into it too much...

unless it are very weird/crappy fans... 4 fans should not be an issue... PWM splitter cable should be good upto 7-8 fans. But brand plays a role. AKASA limits their splitters to 5 fans... to avoid these kind of situations caused by "weird" fans.

But YES, the Swiftech hub is surely the way to go

 

[ATMINSIDE]

hmmm
without going into it too much...

unless it are very weird/crappy fans... 4 fans should not be an issue... PWM splitter cable should be good upto 7-8 fans. But brand plays a role. AKASA limits their splitters to 5 fans... to avoid these kind of situations caused by "weird" fans.

But YES, the Swiftech hub is surely the way to go

My bet is just that the motherboard signal pin can't handle four fans, not an issue with the splitter.

The deal with the Swiftech splitter is that it boosts the signal for the motherboard, so you don't overload the motherboard header

 

[GTXJackBauer]

Welcome to OCFs OP.

That's weird.. does it matter which fan goes where?
I mean, have you tried the 4th fan into one of the other plugs.
It's to determine if its the fan causing it, or if there is an issue with the cable/plug itself.

If the problem "moves" with the fan, then its the fan. If it happens when you plug a fan in the "last" port, then its the cable

Following possibilities:
1. a short in the cable
2. the cable does reports TWO RPM signals
3. somewhere a pin is swiched (note this can be a switched pin/wire on the fan also)

Which fans are you using? Make/Model.

And this is a stupid question.. the cable IS getting power from the PSU through the molex? You're not using just as a fan splitter?

Note: this is an AKASA cable i assume?

Sounds like you're exceeding the limit of the PWM signal pin on the motherboard.

Look at a splitter like the Swiftech PWM Splitter as it actually boosts the signal so that the motherboard sees it as one fan instead of having four fans drawing the signal.
Hope that last bit made sense.

You're both on to something here. I'd say its either one of these things.

When fans don't get a sense of direction, if you will by default they will run full blast as well as my PWM pumps. Something is disabling the PWM. Could be overloading the PWM Header on the MB or a problematic 4th wire.

 

[ATMINSIDE]

Welcome to OCFs OP.





You're both on to something here. I'd say its either one of these things.

When fans don't get a sense of direction, if you will by default they will run full blast as well as my PWM pumps. Something is disabling the PWM. Could be overloading the PWM Header on the MB or a problematic 4th wire.

And if the splitter has a bad wire, you'll need a new splitter.
If the PWM is being disabled from overload, you'll need a different style (read: better) splitter.

$10 for the Swiftech PWM Splitter gets both in one shot
And it doubles the number of fans you can use over your current splitter at the same time.

 

[GTXJackBauer]

$10 for the Swiftech PWM Splitter gets both in one shot
And it doubles the number of fans you can use over your current splitter at the same time.

I agree, the Swiftech PWM Splinter is a great investment. I might grab a couple of those in the near future.

 

[ATMINSIDE]

I agree, the Swiftech PWM Splinter is a great investment. I might grab a couple of those in the near future.

I've got one running five AFC1212D-PWM fans and my MCP35X pump. Doesn't even bat an eye at the power draw.

 

[GTXJackBauer]

I've got one running five AFC1212D-PWM fans and my MCP35X pump. Doesn't even bat an eye at the power draw.

Of course thanks to the molex. As you know for those that don't know or understand it yet, running my 2 PWM pumps on molex with no PWM connection for example will result in them running at full bore hence my no sense of direction comment.

 

[blu4]

Sounds like you're exceeding the limit of the PWM signal pin on the motherboard.

Look at a splitter like the Swiftech PWM Splitter as it actually boosts the signal so that the motherboard sees it as one fan instead of having four fans drawing the signal.
Hope that last bit made sense.

I think that is the option. I am using Corsair SP120 PWM. I've been through 2 splitters already so I know that they are not the problems- fans are brand new. I will be getting the swiftech splitter then. Thanks mate.

 

[ATMINSIDE]

I think that is the option. I am using Corsair SP120 PWM. I've been through 2 splitters already so I know that they are not the problems- fans are brand new. I will be getting the swiftech splitter then. Thanks mate.

You're welcome!

Just so you know, the P8Z77-V LK in my sig is running the splitter off of the CPU Fan header without a hitch.
Full control through AISuite.

 

[blu4]

I only have an Asus M5A99x Evo... I just purchased that Swiftech splitter- for now, 3 fans it is!

 

[ATMINSIDE]

I only have an Asus M5A99x Evo... I just purchased that Swiftech splitter- for now, 3 fans it is!

Here's to good results!

 

[RnRollie]

I think that is the option. I am using Corsair SP120 PWM. I've been through 2 splitters already so I know that they are not the problems- fans are brand new. I will be getting the swiftech splitter then. Thanks mate.

That explains it!
You're not the first to encounter PWM issues with the SP120s... must be some design fault them gobbling up the signal

 

[Bustos]

THIS...

Swiftech

 

[ATMINSIDE]

THIS...

Swiftech

Wow, I thought the Swiftech had a signal booster...

Just adds to my reasons to not recommend the Corsair PWM fans though...

 

[Bustos]

Yeah thats why when you mentioned it had a signal booster I knew I had to find that link again because they state that it does NOT have one.

 

[ATMINSIDE]

Yeah thats why when you mentioned it had a signal booster I knew I had to find that link again because they state that it does NOT have one.

I'm glad you did, that's some good info!