I'm sure you all are familiar with the Xenon 3 pin fan plug header mod that rgall0 came up with ( http://forums.xbox-scene.com/index.php?showtopic=549063 )
That's nice and all, but what if you have a newer phat 360? (Zephyr, Falcon, Jasper) You can't add a plug with no header point. Well, after almost 6 years later, I came up with a solution.
Note: this will work on a Xenon too! (May work on slims, but you'll have to research the 360 power connector's 12v and ground locations)

What you'll need
1. a 3-pin Fan Power Extension Cable (just google it, like "case fan extension cable") (some case fans come with this wire or a 3 pin to 4 pin adapter, just use that... I did )
2. a soldering iron
3. solder (duh)
4. hot glue gun (optional but recommended)

Starting with the extension cable, we need to modify it



We'll be using the numbers off the picture
1) clip that end off
2) you need the ground and 12v pins, but you don't need the RPM pin, so remove it, and the wire connected to it.

next we'll be using the unused hole behind the 360 power connector like in this picture



now pick where you want to solder on the 360's power connector and thread the 2 wires (from the "1" side of the extension) through the hole
Here is the pinouts for the power connector and the hole location



Solder the wires to the coordinating points on the (I recommend tinning the wires before hand)



This is optional after you test the fan, but it is recommended, hot glue the connections to prevent shorting



Here is the finished plug




Now you don't have to solder the fan directly to the 360! You can shorten the fan's wire and plug it up to the connector. No more keeping the fan/case in close proximity when cleaning the 360!

here is how I shortened my wire and what my case fan looks like installed




Happy modding everyone!

Thanks for posting the info. It is method I have used several times to add extra fans but I haven't seen a tutorial for doing this yet. Well done, appreciate you taking the time to post this bit of information.

You're welcome man glad you like it

I just found out that it got added to Tutorials located here.

Definitely something that I'm going to do once my xbox comes in.

Only thing I'd suggest is to strip a smaller piece of wire. If you did originally, then perhaps you had the iron on there too long causing the insulation to melt back. In which case I'd clean the contact points, add some fresh solder to the joints, tin the wire slightly and when soldering it to the points, it should stick right away. This will help to avoid the melting of the insulation as you won't have the heat applied for very long. Don't forget to clean the flux afterwards too. Oh and 30watt or temp controlled soldering iron is better than a 15watt.

The hot glue will work, but the wire shouldn't be exposed that much that it might bridge. In which case you'd kill your PSU and possibly your xbox. Just giving this heads up for anyone else who is about to attempt this mod and is new to soldering.

Totally agree with u man, I did it really fast that's why it came out looking like that, everyone take OR-G's advice

Question about this. My son's xbox had some serious issues with heat and I opened the box up and cleaned it out. I'm looking at replacing the dual rear fans and was looking at increasing their speed to possibly 12v, which they are rated for. I also understand there could be a noise problem with the fans in doing this. So, I was wondering if I incorporated a variable speed device such as the Llamma's Variable Speed Fan Controller 5-12V would removing the rpm pin be a problem considering I'm trying to control fan speed and if so how could I get something like this to work to control the speed of the fans with the Llama's device?

Guess this also can be included here. I'm also looking at jazzing his box up with lights and looking at get the Talismoon Twilight V2 Clear Crystal Flow Wind Tunnel Fan Duct. By description, the air duct draws its power from the dual rear fan connection. The description doesn't say whether the LEDs are rated above 5v or not. So not sure if increase the voltage to the fan port will cause a problem with the increase in power to the LEDs. Thanks

This is a great guide. I seen many on adding a molex connector that way but none with a Fan connector. This is honestly what I was planning to do to mine. I want to run it through a fan controller though so i may have to go with the molex.

Great job anyways