The OOBDETECT_THRESHOLD_* value has changed to 110 for Virtex-5 GTP and GTX. Previously the default value was 001.
When I generate my IBERT, I see the following error:
ERROR:PhysDesignRules:1742 - Unsupported GTX_DUAL programming for comp
OOBDETECT_THRESHOLD_0 general config data setting 001 is not supported. The allowed values for OOBDETECT_THRESHOLD_0
are 110 and 111.
This change is implemented starting with ChipScope Pro 10.1 Service Pack 3 for all Virtex-5 families. It also requires ISE 10.1 Service Pack 3 to be installed so that the OOBDETECT_THRESHOLD_* values used are consistent between the IBERT CORE Generator and the ISE implementation tools.