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_51 ( bus_width__bits_ INTEGER, designation VARCHAR )

### Question ###
Designation of pc800 has which highest Bus width (bits)?

### Accurate SQL ###

SELECT MAX(bus_width__bits_) FROM table_name_51 WHERE designation = "pc800"