Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_11 ( pci_express VARCHAR, memory VARCHAR, sound VARCHAR )

### Question ###
Which PCI-Express has a DDR 266/333/400 Registered/ECC memory and Enhanced AC'97 2.3 sound?

### Accurate SQL ###

SELECT pci_express FROM table_name_11 WHERE memory = "ddr 266/333/400 registered/ecc" AND sound = "enhanced ac'97 2.3"