You can do that by converting string values to binary

IF CAST( 'ALLO' AS varbinary(10)) = CAST( 'Allo' AS varbinary(10))
	PRINT '=='
ELSE
	PRINT '<>'

>Consider the following example:
>
>IF 'ALLO' = 'allo'
> SELECT 'same'
>ELSE
> SELECT 'diff'
>
>I get 'same'
>
>In TSQL, how do I specify that the comparaison shoudl be case sensitive ?
>
>(I've tried with PATINDEX with no luck)
>
>Thanks.