"Cooling After" voltage modding

[Posidon42]

I bought one of these (http://www.directron.com/rd7ca.html) cool little devices last week from Directron. So far I am pretty happy with it, but I want to know if there is a way to mod it so I can have the fans run at full speed. Right now it is taking the +5V off the WOL connector and using that to run the fans. However, my 120mm fans won't run at this voltage.

My initial thoughs are that I am going to be stuck with this, but is there a chance that I can get it to work with +7V or even +12? the +12 would be MUCH better if possible.

Second question on the same modifiation - I can get some 5V voltage regulators from a local parts shop, but they are only rated for 0.5A apiece. Can I put several of them in series or parallel (don't remember which way current works) so I can run some real fans off them? The unit is rated to carry 18W per channel as is.


Also, I am not quite sure how this thing works and what I can change. For instance, it has to be plugged into the WOL connector for it to function. But it also has to be plugged into a fan header on the motherboard for the fan to work. If I unplug the fan from the header (but it is still connected to the Cooling After) it doesn't work. Is the WOL connection supplying power to the fan header??

[Captain Slug]

I'm assuming that it's drawing current from the 5v+ of the WOL and outputting to the 12v- ground. Which is basically an indirect 7V mod, I think.

[Posidon42]

How would I verify this?

[Captain Slug]

Originally posted by Posidon42
How would I verify this?
Do the fans seem quieter right after you turn your PC off? It could run the fans at 12V when the PC is on, then drop them to 7V when the power cycle starts declining.

[Posidon42]

What I meant was how can I verify that it is using 7V verses 5V?

Well I guess I could just measure it... ;)

[N-Bandit]

multi meter.

[KILLorBE]

Originally posted by Posidon42
is there a chance that I can get it to work with +7V or even +12? the +12 would be MUCH better if possible.
Most likely yes, but you're gonna need some parts.

Option 1 would be to build an inverter, but as the power supplied by the +5Vsb is limited I wouldn't recommend this. Also if you increase the Voltage, max. current will decrease, meaning: if the +5Vsb can supply 3A, the max. current supplied by the inverter wil be about 1A @ 12V. Besides that, a high power inverter is complex and can be quite expensive.

Option 2 would be to use a separate PSU/Adaptor and a relay or a transistor, this would allow you to run basicly just as many fans as you want at whatever voltage you wish (depending on the PSU/Adaptor and relay/transistor(s) used).

Originally posted by Posidon42
Second question on the same modifiation - I can get some 5V voltage regulators from a local parts shop, but they are only rated for 0.5A apiece. Can I put several of them in series or parallel (don't remember which way current works) so I can run some real fans off them? The unit is rated to carry 18W per channel as is.
Yes it is possible to run them in parallel, BUT this is not an easy task, I wouldn't bother trying this, another problem would be the voltage drop (~1.5V) across the voltage regulator and the fact that power supplied by +5Vsb is limited.

Originally posted by Posidon42

Also, I am not quite sure how this thing works and what I can change. For instance, it has to be plugged into the WOL connector for it to function. But it also has to be plugged into a fan header on the motherboard for the fan to work. If I unplug the fan from the header (but it is still connected to the Cooling After) it doesn't work. Is the WOL connection supplying power to the fan header??

Most likely the +5V coming from the CA goes thru the fan to the ground of the fan header (Actually the current flows from negative to positive), this way it will only have to switch one connection (it switches between +5Vsb and +12V of the fan header).

Originally posted by Captain Slug
I'm assuming that it's drawing current from the 5v+ of the WOL and outputting to the 12v- ground. Which is basically an indirect 7V mod, I think.
IF that would work it would be a 17V mod, but when the PSU is turned off (Standby) +12V, +5V, -5V, -12V and +3.3V are all turned off, so you can't use -12V.