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Blackandblue
06-11-2009, 10:44 AM
Hey, how can I connect 3-4 case fans that all have a molex end, to the motherboard.? What do i need.


I have a psu that has about 3-4 molex cords with a 3pin connector right at the end of them.

Agent_24
06-11-2009, 10:52 AM
I have not seen any adaptors that let you run molex fans from a motherboard header, only the other way around.

Even if you did do it, You would also have to make sure that you're not drawing too much current from the board. I suspect each fan header on the board is only designed to take 1 fan. Putting 3-4 on one would be a bad idea.


I just daisy-chain all the fans together and then plug them into one PSU molex connector.

If the fan wires are too short, I extend them. All you need is some more wire, a soldering iron (if that) and something to insulate them (I use heatshrink)

Speedy Gonzales
06-11-2009, 10:53 AM
If the mobo doesnt have a header for it then no. You'll have to run them from the molex adapters on the PSU

Blackandblue
06-11-2009, 10:57 AM
So this wont work?
PSU>molex>fan molex>end of the same psu's cord 3pin into motherboard.

Or what about
fan molex end>molex to 3pin adapter>motherboard.

Agent_24
06-11-2009, 10:59 AM
So this wont work?
PSU>molex>fan molex>end of the same psu's cord 3pin into motherboard

If that involves what I think it involves, you'd be trying to power the fan power header with power from the PSU, and a fan in the middle.

I expect there would be a lot of magic smoke

qazwsxokmijn
06-11-2009, 10:59 AM
There are adapters to run fans with 4-pin molex connectors with the 3-pin male headers on motherboards. But running anymore than one fan from one motherboard fan header is not a good idea. I think the max load you should put on those motherboard headers are 0.5A. You'll probably be safe plugging in two 0.2A fans on one, but I personally wouldn't do it.

Speedy Gonzales
06-11-2009, 11:02 AM
How many fan headers are on the mobo?? If there's 3-4 then you can connect 3-4 fans. As Agent said, it may draw too much current, if you connect too many to one header

Blackandblue
06-11-2009, 11:06 AM
There are adapters to run fans with 4-pin molex connectors with the 3-pin male headers on motherboards. But running anymore than one fan from one motherboard fan header is not a good idea. I think the max load you should put on those motherboard headers are 0.5A. You'll probably be safe plugging in two 0.2A fans on one, but I personally wouldn't do it.

ok thanks, so where abouts can I get one of these adapters

Blackandblue
06-11-2009, 11:10 AM
How many fan headers are on the mobo?? If there's 3-4 then you can connect 3-4 fans. As Agent said, it may draw too much current, if you connect too many to one header

P5Q-E

CHA_FAN 1,2,3
PWR_FAN
CPU_FAN

How ever the cpu fan is on CHA_FAN 1. Can you get 3pin to 4 pin for the CPU fan to go on the CPU_FAN for speed alteration, so I can save CHA_FAN 1,2,3 for case fans.

qazwsxokmijn
06-11-2009, 11:16 AM
http://www.cbcnz.com/product_info.php/manufacturers_id/845/products_id/1239?osCsid=0d2c5e870d11e38ec991d81301a47eb4

Agent_24
06-11-2009, 11:22 AM
You can plug 3-pin CPU fans into 4-pin CPU fan headers, no problem

I think you will still get speed control it just won't be with PWM.

qazwsxokmijn
06-11-2009, 11:25 AM
You can plug 3-pin CPU fans into 4-pin CPU fan headers, no problem

I think you will still get speed control it just won't be with PWM.
Yep. that's what the fourth pin is for.