The Board THOL list the hardware Intel has tested with this board before it went End Of Life. http://download.intel.com/support/motherboards/server/se7520bd2/sb/se7520bd2se7520bd2d2tholrev20.pdf .
Assuming you mean SASWT4I, This link takes you to a list of Intel products that were specificly tested with this card. http://www.intel.com/support/motherboards/server/SASWT4I/sb/CS-029917.htm
The AXX6DRV3GEXP backplane is still in used in the newer systems and is on the list as tested with the SASWT4I card (sure hope this is the card you mean) so I don't see any reason to suspect that it would have any issues.
It has not been tested by Intel, but maybe someone else on this forum has given it a try?
Yes you can use SASWT4I with AXX6DRV3GEXP, but SASWT4I is not tested on SE7520BD2SATA, and I also wonder if AXX6DRV3GEXP will fit SC5300 chassis properly.
Yes the cage will fit in the chassi. I am going to try the card/motherboad/chassi tomorrow and will post the results.
Yes the raid cards did work. I ended up trying several and they all worked just fine. I do not know about updtaing the firmware using the built in cabeling since not all were able to connect to the drive cage.
Thanks for all the help