The only way to *really* flush DNS without rebooting Windows. First determine the funky name (not sure what the proper label would be) for your network adapter. It may take some guesswork unless you're smarter than me. On some systems there are obvious labels next to the funky names, on others not. It seems to depend on the driver. Here's the command you type:

devcon listclass net

Once you've got the funky name, edit the following script to your needs and save it as a .bat file. This is the script I use on my own system:

REM flush DNS cache
ipconfig /flushdns
net stop "dns client"
net start "dns client"

REM To list all adapters of any system run the following command:
REM devcon listclass net

REM Disable/enable LAN adapter
devcon disable "PCI\VEN_8086&DEV_101E&SUBSYS_05491014&REV_03"
devcon enable "PCI\VEN_8086&DEV_101E&SUBSYS_05491014&REV_03"

REM To disable WIFI adapter
REM devcon disable "PCI\VEN_168C&DEV_1014&SUBSYS_833117AB&REV_01"
REM devcon enable "PCI\VEN_168C&DEV_1014&SUBSYS_833117AB&REV_01"