LLMNR can impact network performance in Windows 7. This can especially take place with connections to SQL.
See our article on LLMNR for Group Policy or Network disabling or use the following:
Open a Command Prompt as an Administrator (CMD in the Search box)
Type the following:
REG ADD “HKLM\Software\policies\Microsoft\Windows NT\DNSClient\
REG ADD ” HKLM\Software\policies\Microsoft\Windows NT\DNSClient” /v ” EnableMulticast” /t REG_DWORD /d “0” /f
(The second command is one line!)