TRUE Push / Pull Question

[rjbarker]

I'm just trying to figure out some "Fan Upgrades" now that I have me Rig in pieces.
I would like to add another 120mm Fan to my TRUE, right now it is "pushing" mounted on the Memory side, so would like to add a pulling to the opposite side.
Question, the Fan on their now has the standard 4 Pin to plug directly into the Mobo at the CPU Fan Header, would I somehow connect both Fans together and plug them into the single 4 Pin CPU Header on the Board? If so which plugs would I want on my second Fan for Pulling? My first TRUE Fan just has the single 4 Pin connector.
Anyone with Pics of this Push / Pull plugged inot the CPU header on the Evga X58 could you possibly Post them up...

EDIT: Sorry guys..just doubled checked my Fan that came with my TRUE and it is a 3 Pin, not a 4 Pin....the Classified Board has a 4 Pin CPU header, its no biggie to plug in a 3 Pin to a 4 Pin header?

Thanks guys.

[MpG]

Yeah, 3-pin into 4-pin header is fine, just match up the notch like any other fan header. The fourth pin is for PWM fans only, but the other three are standard. As long as you weren't overloading the header, you could even run a splice and run both fans off a single header. Prolly more trouble than it's worth though, since there should be other headers nearby to work with too.

[rjbarker]

Yeah I'm just kinda figuring out all this Fan plug stuff, from what I understand as you say PWM Fans, is this the ability to "control" the Fan speeds, as in Speedfan or the BIOS? If so, my old Evga X58 Board had no 4 Pin Headers, they were all 3 Pin headers except the CPU...
So, if I want to connect the 2nd 120mm Fan to the First 120mm Fan how do I connect them and then plug into the CPU Header? Sorry...just learning all this Fan Header , 3 Pin , 4 Pin and Molex stuff now...

[MpG]

PWM = Pulse Width Modulation. Basically, instead of undervolting a fan, it delivers intermitent pulses of full voltage. So not only can you control the fan speed, you can actually do it more efficiently (since you're not wasting power across a resistor/regulator), and you can sometimes slow a fan down even further than undervolting would allow. But yeah, most motherboards only over one 4-pin header for that, meant for the CPU.

Splitting up the power draw involves using the appropriate parallel splitter. For 3-pin headers, it would basically look like this:
Attachment 4867
You can often get find them in electronics sections of surplus stores or computer shops under some generic parts brand for a few bucks, if you're not inclined to make them up yourself.

[rjbarker]

Right on thanks for that MPG....looks as though I have a lot to learn in the way of "Fan Power Connectors indeed"...
How about these questions, seeing as how you have the "knowledge"....:
1. When I disassembled my Mobo one of my Fans had a 4 pin Molex and a single wire (yellow) 3 pin connector, of course the molex connector was plugged into my PSU Molex, now the single wire / 3 pin connector (female) was plugged into my Mobo 3 pin header, this was only so the fan can be "monitored" is that correct?
2. If I get a fan that only has the 3 pin female connector, is thier an adapter available so that it can be plugged into a Molex connector?

Two things I want to do when I get back in a month from work and assemble my Classified Mobo and Rig:
1. Change out the Silverstone 1200 RPM intake fan (blows air into the case onto the GPU's - TJ09 Case draws in from the sides) with a higher rated Fan, as in a 1600 - 1800 RPM to provide a little more Air.
2. Add the "pull" fan to the TRUE

Now, if I purchased the one 1600 - 1800 RPM intake fan for the case, would it be wise to use the Silverstone 120mm as a "pull" fan on the TRUE..I ask cause the Push Fan is a 1500 - 1600 RPM, I guess it would be optimal to have both the Push and Pull equal RPM?...Or would I be alright to have the "push" higher RPM then the "pull"...basically seeing if I could purchase one fan and switch the replaced fan to a "pull" fan on the CPU...

Thanks a ton!!

[486]

Pull wont be as effective as good case intake/exhaust fans.

[rjbarker]

Pull wont be as effective as good case intake/exhaust fans.

uuhh..no kidding....its a "push / pull" arrangement I'm looking at and increasing the CFM of one intake Case Fan
Presently I have 5 x 120mm Scythe S Flex.....for Case Exhaust / Intake

[MpG]

Some fans actually come with 3-pin to molex adaptors like this, but I expect there's a decent chance of finding a basic version in the same place as the aforementioned 3-pin splitter (If you pick a few up, you also have the option of switching the 12V wire in the molex plug over to the 5V wire, making for a quick way to undervolt the fan to 5V).

As long as you have something between them (i.e. the heatsink), adding the second 1200rpm fan should still help out, especially on a heatsink like yours with dense fins. I'm fairly certain that you'll want the faster fan doing the pushing, though.

[rjbarker]

you also have the option of switching the 12V wire in the molex plug over to the 5V wire, making for a quick way to undervolt the fan to 5V).

I've heard n read this "undervolting" fans in a few cases...what exactly is the benefit to this?....
Also, can it be "too hard" on a Mobo / Power by plugging fans into all the available headers and not utilizing the Molex connectors at all?

Thanks again for sharing the knowledge...appreciate it!

[enaberif]

Undervolting a fan makes it spin slower which is less noise but some fans can still output good air flow.

I personally don't condone doing this as you can buy resistors to do this properly and not have to worry about voltage back feeding into components or your powersupply.