Usage:

ipconfig [option]
where option is one of:
/all -- show all information
/renew [Adapter] -- renew adapter or all adapters if none provided
/release [Adapter] -- release ...
/flushdns -- flush dns registrations
/registerdns -- static refresh (causes dns registrations?)
/displaydns -- show dns cache
/displayclassid Adapter -- show class id info
/setclassid Adapter ClassId