You can download it from http://www.ziddu.com/download/8839931/DellOptiplexGX280Graphiccarddriverforwindowsxp.zip.html
or go to the below link and download all the drivers http://support.dell.com/support/downloads/driverslist.aspx?c=us&cs=19&l=en&s=dhs&ServiceTag=&SystemID=PLX_GX280&os=WW1&osl=en&catid=&impid=
you have to select the operating sysgtem and you can see all the drivers available
Answers & Comments
You can download it from
http://www.ziddu.com/download/8839931/DellOptiplexGX280Graphiccarddriverforwindowsxp.zip.html
or go to the below link and download all the drivers
http://support.dell.com/support/downloads/driverslist.aspx?c=us&cs=19&l=en&s=dhs&ServiceTag=&SystemID=PLX_GX280&os=WW1&osl=en&catid=&impid=
you have to select the operating sysgtem and you can see all the drivers available
Please visit:-
http://support.dell.com/support/downloads/driverslist.aspx?c=us&l=en&s=gen&os=WW1&osl=en&catid=&impid&SystemID=PLX_GX280
Good luck & happy computing!