I am facing a strange problem

When I am launching the driver with the below command:

#io-net -i1 -d i82544 mac=id,speed=100,duplex=0x1 -ptcpip prefix=/sock1

The connection seems to be proper.

But when i don't mention speed and duplex i.e. when i give the following command

#io-net -i1 -d i82544 mac=id -ptcpip prefix=/sock1 (command used for auto negotiation)

The other nic card is unable to see network connection (says network cable unplug) 

Network configuration (82544 Nic direclty connect to laptop via straight cable).

The obervations sloginfo looks same for both commands and io-net does't show any error.

Please suggest what may be te issue