Volt modding case fans to 7v

[machinist]

Heard a lot about this, and wanted to know a bit more.

Can't locate any instructions on how to volt mod down to 7v for case fans. Anyone got a linky ?

Ta

[BlackDwarf]

Variable inline resitor?

One of these?

[arthurleung]

Simple

Take a toothpick and use it to get the ground-pin out, then exchange it with the 5V (i.e. black goes into where red is)

But just make sure you DON'T hook the fan up to other non-fan devices down the chain with this simple mod.

7V to components could be destructive.

[herulach]

if its for a molex connector then swap the ground wire on the fan connector to the 5v space, at the opposite side to 12v so your connector should go from:

________
|            |
|            |
-----------
  | |

to
_________
|             |
|             |
-------------
  |         |

[FatalSaviour]

Are you talking about wiring the fan to the 5V and 12V lines of your PSU, to get your 7V, or a proper controller?
http://forum.overclock3d.net/showthread.php?t=245
You need to take more care doing the first 7V tricks, and something like the Zalman Fanmate, or any other Fan controller will probably do you better.

[machinist]

Perfect, thanks guys

[amjedm]

I'm not sure if i've got two 'mods' confused, but doesn't this feed some voltage back into the psu and therefore you require a quality psu to begin with?

Another link

http://www.silentpcreview.com/article63-page1.html

And another one

http://www.silentpcreview.com/article6-page1.html

[herulach]

a little tiny bit maybe, but not a great deal, and ive done it on all manner of psus, including a crappy 5 pound ebuyer one

[FatalSaviour]

I'm not sure if i've got two 'mods' confused, but doesn't this feed some voltage back into the psu and therefore you require a quality psu to begin with?

Another link

http://www.silentpcreview.com/article63-page1.html

And another one

http://www.silentpcreview.com/article6-page1.html

That is correct, hence the "You need to take more care doing the first 7V tricks".
You're meant to use up any voltage that's being returned to the PSU with another component, but how dangerous this actually is is up for debate.

I'd recommend just getting a fan controller or some sorts...as they're not particularly expensive, and will put your mind at ease .

Scan do the Fanmate for starters

[amjedm]

That is correct, hence the "You need to take more care doing the first 7V tricks".
You're meant to use up any voltage that's being returned to the PSU with another component, but how dangerous this actually is is up for debate.

I'd recommend just getting a fan controller or some sorts...as they're not particularly expensive, and will put your mind at ease .

Scan do the Fanmate for starters

I've always stuck with fan controllers (have fanmate models 1 and 2, have bought some Titan branded clones as well). I also use a Sunbeam Rheobus and the Coolermaster Aerogate 2.

I've been running 2 fans off the one fanmate as well so you may only need 1?

To the OP - there is currently a thread in the bargains section for a Coolermaster fan controller - you may want to try that.

[-ChEM-]

i thought no PSU will tolerate current coming back through a supposedly positive wire

thats why the 7v trick is dangerous when you have nothing else on the 12v rail you are using

you need to put a hard drive/optical drive/something on the same rail so that the amount of current put out down the 5v line by the fan as negative is less than the amount that the hdd/whatever is using as positive, making it overall positive again

im pretty sure a single optical drive or hard drive, maybe even a floppy drive will be ok but i always forget about plugging in the fans until im also going to have most other things plugged in, even if i dont connect up IDE/SATA cables yet

and its important to be aware of this if youre selling stuff on ebay and that kind of thing as it will be your fault if they dont know the stuff you sold them isnt supposed to be used on its own

[scrandman]

You can avoid all of the issues with "feedback" and such like by using the 5V mod instead. Simply swap the red & yellow wires on the 4 pin molex. If you are using the "pass through" type molex connectors on a fan then do the mod on both the male & female connectors - you can then run other things downstream of it. Never mod the molex connectors on the PSU itself, as it could get confusing at a later date...

[-ChEM-]

some fans wont spin up at 5v but its worth a go

[scrandman]

some fans wont spin up at 5v but its worth a go

True, but I've never found one myself.

[fullfat]

yeah, some need a higher voltage to sort of 'kick start' the ram and get it going
its really easy though, even i could do it