Asus Q-fan

[54regcab]

I have an ASUS A7N8X with the "q-fan" technology.
I would like to connect my case fans to the mobo but the fans are 2 wire and use standard power supply plugs.

1: Will "qfan" work with fans that don't have the speed sensor lead ?

2: Can an adapter be purchased to convert the 4 pin into a 3 pin plug ? I have seen 3 to 4 but not 4 to 3. I could "fabricate" an adapter if the mobo will support q-fan.

[DanceMan]

I would doubt that your fans would work with Q-fan and also doubt they can be converted. I have a Panaflo 80mm "L" fan with two leads. It has a connector for a three-wire plug lead, but there is no sensor in the fan to support it.

[54regcab]

Looks like it's the +7V mod for the case fans then

[DanceMan]

Suggest you do it with resistors or a pot, and not by connecting across the +5 and +12V leads. I've seen a post at Silent PC Review that gave good reasond for not doing that. And it made me wonder about the K7T Pro and Duron 1.2 I killed. I think the voltage regulator chip on the board may have failed -- apparently weak. All the +5V pins on the mobo/ATX power connector were burnt. Pretty sure my case fan was at 7V across the 5 & 12V pins. I won't take the chance again.

[SexyMF]

I believe speedfan will allow you to manually throttle your fans even with the RPM input line.

[K62]

Originally posted by DanceMan
Suggest you do it with resistors or a pot, and not by connecting across the +5 and +12V leads. I've seen a post at Silent PC Review that gave good reasond for not doing that. And it made me wonder about the K7T Pro and Duron 1.2 I killed. I think the voltage regulator chip on the board may have failed -- apparently weak. All the +5V pins on the mobo/ATX power connector were burnt. Pretty sure my case fan was at 7V across the 5 & 12V pins. I won't take the chance again.

hmmm :S I have been running my cpu fan at 7v by the +5 and +7 volt leads for about 2 years now with different boards. I will have to look for that article you mentioned though... im a bit worried now.

[SexyMF]

Well, I've just taken chunks out of 2 of my fingers testing speedfan with a Delta fan

With regards to the 7V mod:

Your PSU provides your power rails essentially in the same way as a transformer. There is a winding for the 5V and the same for the 12V lines. Now the PSU is regulated by sensing current draw on these loops. When you put a fan across the 5V and 12V you are redirecting current paths. This can upset the load sensing for the PSU. But mostly any decent PSU doesn't care so much about the puny amount of power a fan takes.

[K62]

ah ok! thanks for that SexyMF. So it is pretty safe to say that if this hasnt caused my Antec any problems in close to a year, that im safe?

[DanceMan]

In the thread I couldn't find (must be in psu, couldn't find it in fans) there was info on the construction and circuitry of psu. From what I can remember, the 7-volt mod doesn't present the same problems to all types. Your Antec is probably much safer than my generics.