Bad information mostly. I was under the impression that the Intel Server configure would warn you if you left a component out. I guess it missed that I didn't add a SAS module or a raid card. I was under the impression that it would work directly from the board. I never have found any info on the expander cage beyond the installation instruction.
Long time ago, it was even more confusing for boards like S5000XVN, it came in different flavours S5000XVNSATAR or S5000XVNSASR etc.
Customer used to get S5000XVNSATAR with an expander backplane and thought that it was going to work. Unfortunately, it would never work as Edward said above, expander backplane works with sas controller.
Customer was left with fw options either:
1. change the expander backplane to non expander
2. change the board to S5000XVNSASR as it has got a sas and sata controller.
3. Buy a validated raid SAS controller adapter.
A document called spare parts and lists were sometimes useful to check before placing an order.
All the best,