It runs a PIC18F2450 that interfaces with the USB as a virtual com port.
Unzip the m4atx.zip file. There should only be one file inside m4atx.inf.
Plug in the M4 atx if you havent already done so.
When the found new hardware wizard pops up, select install from a specific location.
Click next and select this attached inf file.
After thats done it should appear as a com port (ie COM4).
But if the new found hardware wizard doesnt pop up when you plug in the M4 ATX then it might be a bug in their firmware.......
Maybe you can use hyperterminal to communicate with the m4 atx, but I dont know any of the commands due to lack of documentation.
I will try this as well as soon as Laci, Andrei and I can figure out why my m4 doesnt send the motherboard pulse when my m4 is in the hardoff mode, and I can get a suitable header for the cable to plug into the motherboard's usb header.