The MIG v3.1 tool allows selection of different Additive Latency values on the Memory Options screen.
However, the DDR2 and DDR3 Virtex-6 MIG designs only support an Additive Latency value of 0.
Please ensure that the Additive Latency selection in the MIG tool is set to 0.
Non-zero values are not supported.
This option is removed from the MIG tool in MIG 3.2.