Has any encountered issues where while scrolling through a spreadsheet sections of the grid and even data within cells disappear? At first i thought video card or ram but i have had the problem running on a Dell Precision 480 WS with XP 64 with 8GB of RAM with an Nvidia Quadro FX3500 card and also recently with a Compaq EVO XP 32 with 1GB of RAM and an Nvidia Vanta Card. Any ideas as to why this is happening?