Have a 16 core 16G box with two pro/1000 mt dual port server adapter and Intel 82546GB onboard NIC chip. When we connect one card to our data network to receiving UDP multicast, we drop a lot of packets. OS is 64 bit 2008 server standard. Seeing one core running CPU. Is it due to nic processing done by one CPU? How do I check if receive side scaling is working ok?