[Dabamf]

I know this has been gone over (at least I think) but I can't find it anywhere and I'm about to start my first build. Is it ok to plug fan power connectors into the mobo headers, or should I invest in a couple 3-4 pin molex adaptors? Is the same applicable to cpu fans?

I don't plan on using any extreme fans, just 2x120mm enermax adjustable and a 92mm 3-blade low speed delta for cpu (2800 rpm).

[Aphex_Tom_9]

it should be okay

[MVC]

I'm running 3 Evercool 120s off of the mother board headers (intake, exhause, CPU) on an Asus P5GDC-V board without any problems. But, to be sure, you can check the specs on your mother board to see what the headers can take and then check the specs on the fans to see what they draw.

[Ven0m]

Enermax fans draw only a little power, so they will be safe for any mobo. I'm not sure about Delta power, but as you say it's low-speed it should be safe too.

[yeha]

the rule of thumb i've heard around for a while is that you don't want to draw any more than 4 watts out of a single motherboard fan header. so if your 12v fan is rated for 0.3 amps, you're just skirting with the maximum recommended.

of course, some motherboards will be better or worse than others in this respect, and it's rare that the manual will even mention this limitation. there's not much you can do apart from emailing the manufacturer, finding a forum post by someone who tried it already, or risking your own parts.

best to just stick with silent fans that draw 0.1 amps or so, as we silent freaks have been doing forever

[mortimer]

Any thoughts on this combination? MSI KT400 Ultra 400 FISB. Has three fan headers. One for CPU, two for system. Looking to use Panaflo 92mm M1 on CPU, Pabst 120mm 4412 on rear, and Vantec 92mm SF9225L on "front".

[joelkyr]

here is a link regarding fan on MOBO connector:

http://www.ocforums.com/showthread.php?t=363889

[Sneaky]

mobo headers can power fans up to 8w, but i would truly never run any fan more than 5w off of my mobo headers - hell, i don't dare run any fans off of my own headers except for my little chipset fan (mainly for power loss to other mobo components - remember that these are being powered by the ATX connector, so its pulling power directly from the mobo rather than the PSU

[yeha]

Originally Posted by mortimer

Any thoughts on this combination? MSI KT400 Ultra 400 FISB. Has three fan headers. One for CPU, two for system. Looking to use Panaflo 92mm M1 on CPU, Pabst 120mm 4412 on rear, and Vantec 92mm SF9225L on "front".

hrm just wondering why the mix of fans - the vantec stealth fans are notorious for buzzing, clicking, whirring and chugging almost all the time - i know the 3 vantec fans i've owned have been awful from a silencing point of view.

if i was going for silence (and my budget was limitless ) i'd go with two 92mm nexus fans and a single 120mm nexus. why? because although nexus doesn't manufacture their fans themselves, they order in huge quantities and only sell the best of the bunch - their 120mm fans (originally yate loons) are of amazing quality, and almost every one you buy is just as good as the last - no per-sample variability that you get when you buy fans straight from the manufacturer or a plain-old rebadger like vantec, coolermaster or enermax. their 92mm fans are the same from what i've been told, though they're originally made by dynaeon i believe.

anyway, the fans you listed draw such small amounts of power that you shouldn't think twice about plugging them into the motherboard headers. i would definitely reconsider the vantec fan however, the motor noise still echoes in my head.

[MVC]

I think motherboards are now being made to handle higher power requirements, at least those with the 24-pin ATX connector. The instructions for my Asus board read "the fan connectors support cooling fans of 350mA ~ 2000mA (24W max.) or a total of 1A ~ 3.48A (41.76W max) at +12V." I still don't think I'd want to plug in several 9-10W Deltas even if the board says it can handle them, but low speed fans definitely shouldn't be a problem.

[mortimer]

The Pabst and Vantec were *free* from a friend. The Panaflo is recommended for the SI-97 heatsink. Might not use the Vantec (or any front fan) as it looks like a real pain to mount/maintain on this case (recycled from a Gateway 950, layout is similar to Antec Sonata). Also got free MB, 1024 3200 Samsung RAM, and an FPS group PS. Thank you for your replies!

[RoadWarrior]

None of my mobos have any specific instructions on how much the fan headers can take so anything over 350mA goes on a molex. Actually in a system with that extra "P4" 12V connector on, that is unused by my mobo, I cut part of the atx socket off a dead mobo and wired my fans into that, and plugged it into the "P4" 12V connector, saves using up drive molexes and lets you route that wire away from all the drive bays instead of having extensions and passthroughs strung back and forth.

[MVC]

Originally Posted by RoadWarrior

None of my mobos have any specific instructions on how much the fan headers can take ...

I didn't see any info on my first glance through all the stuff included with the board, but then, instructions are what I read when all else fails . Anyway, I'd e-mailed Asus trying to find out, but they never responded, so one night when I couldn't sleep I read everything and came across the header specs.

120mm fans are no longer unusual or uncommon and I have a feeling motherboard manufacturers are basically trying to prevent RMAs--knowing that many (most?) people will just buy a fan and plug it in. And, if someone is only using 1 fan per header, as recommended, even powerful fans probably wouldn't kill the board, at least not while it's under warranty.

[Ven0m]

ASUS boards can handle pretty much, but I'd ratehr not connect to mobo anything over 4-5W.

[MVC]

Originally Posted by Ven0m

ASUS boards can handle pretty much, but I'd ratehr not connect to mobo anything over 4-5W.

Ah, but you read the specs I have a feeling Asus, and maybe some other manufacturers are building for people who don't read the specs. As for myself, any fan over 4-5W needs to be on a controler, not because the board can't take it, but because the thing is bound to be noisy and I'd want an easy way to turn it down.

[mortimer]

Thank you all for your help! Max, did converting the P4 connector cause any problems?