What are you trying to display? If you are trying to flush a table to the browser, it will not display until you reach the end of the table. This happens because the browser needs to calculate the width of each cell in the table before it starts drawing.
There is a workaround for this in IE5, Netscape 6 and Mozilla. You can declare a table as <table style="table-layout:fixed"> and then explicitly declare column widths:
<col width="40"><col width="60">
If you do this, the browser will draw the table row-by-row as it receives the flushed data, rather than waiting for the whole table. However, this will not work with earlier browsers. (See the CSS2 specification at www.w3c.org.)