Using "not equal" instead of "different" operators

Hello
I have just read that the "=" has a better performance than "<>", which makes me think that I should use "NOT =" when trying to express inequality. Now, if it is so, why the query engine does not do that internally? In other words, should not the operators "=" and "<>" perform the same?
Thanks a lot.

Well, I have read here http://www.sql-server-performance.com/tips/t_sql_where_p1.aspx that operators influence how fast the query perform.
Now, when I wrote "NOT = " I tried to simplify writing "NOT (Value1 = Value2)".

For performance it is probably better to split "value1 <> value2" like this: "value1 < value2 AND value1 > value2"
In this way SQL has better change to benefit from indexes (if exists).

[quote user="Madhivanan"]
Did you mean this?
value1 < value2 or value1 > value2
[/quote]
Yes, off course, my mistake[:S]

i did the following query , with execution plan. i comment every query with the result of plan:
using "="
--index seek
--relative to batch 11%
--subtree cost 0.003
--estimated IO cost 0.003
--estimated rows: 1

select * from Production.Product
where ProductID =5
-----------------------------------------------------------------------
using "<>"
--index seek
--relative to batch 44%
--estimated IO cost 0.012
--subtree cost 0.012
--estimated rows: 503

select * from Production.Product
where ProductID <>5
-----------------------------------------------------------------------------
using < value1 or > value2
--index seek
--relative to batch 44%
--estimated IO cost 0.012
--subtree cost 0.012
--estimated rows: 503
select * from Production.Product
where ProductID <4
or ProductID >6

conclusion:
- all cases activate index seek , so no performance lost
-you find "<>" equivalant to "< value or > valu" in performance.
- using "<>" operator has no disadvantage , the only effect is the expected number of rows and consequently estimated IO cost
- it seems "=" better , but realyy it is not , bez it returns only one row , with 0.003 cost , but others returm more than one row and consequently do more IO
-if query return less rows , that is best IO

so, don't bother yourself with "=" or "<>"