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Help neeeded: setting up fans directly off PSU

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anitract

Member
Joined
May 28, 2004
Location
Trullion: Alastor 2262
First computer build. I need help making sure I have all of the components (cables, adapters, etc.) that will be needed to set up my 5 fans (3 case, 1 blowhole, 1 heatsink) to run on a line directly from my computer's PSU, while still maintaining the ability to monitor the fans RPMs.

Here is what I have already:
+Fortron FSP400-60PNU-R1
+5 Panaflo H1BXs (80x80x25mm, 39.6 CFM @ 2950 RPM, 32.0 dBA, 2.08 watts, 173 mA, 12v DC, 3 pin Molex connector)

In terms of getting the fan off the PSU, here are my questions:
I want to put 5 fans off of my PSU...that's 4 case fans and 1 heatsink fan. They would all be Panaflo H1BX's. Is it possible to fit all of these fans off of one 12v PSU line...i.e. can the line handle the wattage (pardon my ignorance of power supplies)? If so, what kind of "line splitters" do I need so I can do this (a link would be appreciated as to where I could find it too)? If not, what should I do?

I will also be getting a controller like the Sunbeam that is so highly recommended. Do I need any additional power cords to do this ontop of the fan-on-psu configuration?

Sometime in the future, I want to be able to display the RPMs on a Matrix Orbital MX series LCD display. Here are my questions:
Do I need to use something like this?

Sorry for the many questions, but I want to order everything I need in one order so I can set my system up ASAP! I'd really really appreciate any expertise anyone could offer. Thank you!!!
 
What you plan to do now and what you want to do in the future seem to conflict with each other. Let's stick with what you want in the future. You want to be able to monitor all of your fan speeds.

To do this, the fans must use the 3-pin connectors AND have 3 wires. For now, get as many fans as you have headers for on your MB. Your MB manual should point out all of your fan headers. You are limited by the # of fan headers. You can't put 2 + fans on any single header because the header can only read the signal from one fan. Multiple fans would yield incorrect readings.

Later, when you get your fan bus, you should be able to switch the fans over.

The 4-pin molex connectors can not be monitored. However, they have pass-through connectors that allow you to chain them together.
 
Ok, let's see if I understand this. I cannot put BOTH all my fans on molex/PSU line AND use a RPM Passthrough cable to display the RPMs on an LCD display, because you need all 3 wires in order to monitor RPMs?

To put it another way, I can't connect my fans to the passthrough cables and then take the single RPM wires of the passthroughs and plug them into my LCD display, because you need all 3 wires of each fan to monitor RPMs.

I guess I didn't understand the use of the RPM passthrough cable. What is it used for then if you can't do what I wanted?
 
hmm, i'm getting confused. Plug a 12V+/- line from the PSU into the fan bus, the plug a fan into each connector on the fan bus. If you run out of room, get a splitter for the fan bus connections. If the fan bus has RPM monitoring, the fan bus can display the speed if the fans are connected to the fanbus with the 3-pin cables
 
Searching through my motherboard (Abit NF7-S Ver. 2) documentation, the only references to fan connections are the CPUFAN1, PWRFAN1, CHAFAN1, and J10 headers...according to the documentation they are to connect the processor fan, power fan, back chasis fan, and northbride fan accordingly. Is this what you mean by fan bus, because I'm not entirely sure what that means?

I read this thread , which is what made me think that I didn't want any fans connected to the motherboard, rather on a separate line. So am I confused?

I currently have 2 front fans, 1 exhaust, 1 blowhole, and one processor fan. If I do want to connect them to my motherboard. What should I hook up to which header, since I seem to only have 4 headers?

I am a total newbie at this, which is why I am asking so much. :)
 
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Ahhhhh...ya know, I knew that, in another context it I would have made the connection! Oh well...

Anyway, I think it's possible to use the RPM passthrough in order to get RPM info from fans that are connected to a fanbus that has no RPM monitor capability. I simply use the passthrough line to another device that can read it (such as the motherboard).
 
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