In order to solve the USB disconnect problem:

1. Add a pci usb card (either 1.1 or 2.0) to your computer; or

2. Add a powered usb hub (either Belkin or Linksys) to your computer.

Either hardware will solve your problem. It will create a more "robust" usb connection.

For background, see:
http://forums.us.dell.com/supportforums/board/message?board.id=aximactivesync&message.id=24

Make sure when you view this link that you copy the entire address.