update performance

i am trying to update 300, 000 records using a join and a condition, it takes around 11 min, the time is too lons, i want it to be in seconds,

the schema of two tbles is given below:

pat   hospid  pattype   patno hospid pattye

1    12        I                      1         12       null

2     12       I                        1         12       null

there is a clustered index on both the tables on patno, hospid, i am trying to make the patye of the second tale to that of dirst table based on certain criterion on other cokumns  in the first table that are not shown above, please advice

thanks for any help

nik