Poking around a bit http://h20564.www2.hp.com/hpsc/swd/public/readIndex?sp4ts.oid=403747&swLangOid=8&swEnvOid=1093
It looks to me like that 5000 Small Form Factor is pretty old. The drivers I'm seeing, including the BIOS looks like from 2005 or earlier.
You may be stuck with actually seeking the drivers from the actual device manufacturer, by identifying the individual components using device manager, properties, details tab, Hardware Ids and then using google to find them.
In the case of Intel products you might have some luck with the driver update utility from here http://www.intel.com/p/en_US/support/detect
But you may be forced to actually use there download center after identifying the individual device.