Try <table style="width: 750px; margin: auto; text-align: left">.......</table>
if your table is not in a containing div
or if your table is inside a div tag this may also work:-
<div style="width: 750px; margin: auto; text-align: left;">
<table>......</table>
</div>
or
<div style="width: 750px; margin: auto;">
<table style="text-align: left;">......</table>
</div>
The div with a fixed width with margin: auto will centralise on the page but the text should align to the left.
You may have to delete any other alignments like align="left" and align="center" in case they co***ict. Without seeing your code I can't be sure what will work.
Code downloaded to my PC will be deleted in due course.
WIN7; IE9, Firefox, Opera, Chrome and Safari for Windows; screen resolution usually 1366*768.
Also IE6 on W98 with 800*600 and IE8 on Vista 1440*900.