IIF in SQL

hello!
In MS ACCESS 2000, I can use the IIF function like (
SELECT IIF(x>0, "True","False") from x_table.
I tried the ISNULL but got a wrong ouput.
How can I do this also in MS SQL?
Please help...
Any effort is higly appreciated.
Thanksselect case when x>0 then 'True' else 'False' end
from x_table

rudy