Ajax Delay and Flicker

I have a simple Table, 1 Row 2 Cells . The first cell has the Menu.
The second could have anything.
I update the 2nd Cell with the code below.
The problem is that the table elongates up and down for a split second
before the image is displayed in the cell.
I was able to slow it down by running a bandwidth intense program in
the background and I saw it elongate(The table border stretched also)
It happens DURING "document.getElementById
("Content").innerHTML=newTD;" , not before
The Cell I'm updating is id "Content". Do I need a div???

xmlResponse = xmlHttp.responseXML;
// obtain the document element (the root element) of the XML
xmlDocumentElement = xmlResponse.documentElement;
imageName = xmlDocumentElement.firstChild.data;

newTD="<img src='"+imageName+"' width='650px' id='Graph' />"


Any Help