When trying to do a clean install of Windows XP on a HP dc5750 workstation your device manager may be showing SM Bus Controller as an unknown device. Go to: http://welcome.hp.com/country/us/en/support.html and enter in dc5750 as your product. After choosing Windows XP as the Operating System, scroll down to the Chipset section and download the ATI Chipset Driver for Microsoft Windows XP Driver (sp33927.exe). Double click on sp33927.exe to extract it to a folder on your C drive (C:\SWSetup\sp33927). In device manager for the SM Bus Controller device, click on update driver and browse to the C:\SWSetup\sp33927\ folder to install the software.