As Neil says you will not be able to use the Dell proprietary connection to connect to another Mb. I have succesfully cut and soldered the wires to connectors i took off a front panel of a junked computer. The connectors looked like these.http://www.extremete...,1149953,00.asp
I use shrink tubing to cover the solder joints. You will have to determine which wires are used in the Dell switch button for the correct use. Dell, in their wisdom, does not use color coding on the wires in the standard way. On the startup botton you will need to use a multimeter to find which wire is reset and which is power on. I used a common ground between the two switches( i soldered 2 connector ground wires to single switch ground wire). I also made a diagram of each wire coming from the dell switch( and lights) and labeled the wires so i know what wire was power and what was ground. Some of theses connectors it does not matter which way they are connected as the connection is just a passthru for the power( lights)that is controlled by the motherboard. Using a multimeter to check continuity while pushing the power on switch on and off will tell you which wire it is. on the dell i worked on the black wire was the ground wire on the switch. The gound wires on the connectors from the junked computer uses the white wire as the ground wire. It will look funny as white is connceted to black, red is connecter to green or orange, etc, but that is the nature of doing this kind of mod.
If you really do not want to splice wires together you can buy a tool that will push the connector wires out of the connector so you can put them in the type of conectors shown on the above website. You can get this tool here.http://www.coolerguy...0556056768.htmlhttp://svcompucycle....ving-tools.html
If you really cannot find a junk case somewhere to steal the connectors from you can use these. They are kind of short but useable with modding.http://www.xoxide.co...ontrol-kit.html
ACC, the only thing i can say now is welcome to the world of MODDING. I have been doing this for a while now and find it great fun to build computers that when you open them up you cant see any wiring.