I've got a Windows 2008R2 standard server running DHCP services. We've noticed that certain clients are receiving inconsistent DHCP replies. We have over 175 Windows workstations in this VLAN that don't seem to have trouble getting DHCP leases. However, PXE-booting clients trying to reach our DHCP server are able to get a lease inconsistently. Additionally, we tried using the "dhcping" tool against our DHCP server and found that roughly two of every three requests time out with "no answer" -- and this holds true when we set the timeout value on dhcping to 20seconds. After a failed attempt, however, we may get a dhcp lease reply immediately with dhcping. This leads me to believe that this issue isn't confined to PXE booting clients, but something more systemic with my LAN layer2 or DHCP. And that possibly my 175 windows clients are experiencing this in some form without my knowledge. We have over 30% of our scope available so the addresses are there. I was unable to find anything in the Windows server "DHCP-Server" log. Of course, my goal is to have my DHCP server reply to every request that it receives on the LAN!