|Dell's website still hosts drivers for their products back to MS-DOS.|
The most helpful thing you can do is tell us the Service Tag. On the back of the tower usually 5-6 alphanumeric characters, sometimes includes a barcode. You enter this on Dell's website and it will provide all the drivers necessary for your computer, including the F6 utility.
Many old servers used the Adaptec AIC series drivers, at least my old HP Vectra XU 6/200 Dual Pentium Pro machine does.
iMac G5 1.8GHz "Hero" PowerPC
2 x 1GB DDR PC3200 SDRAM
160GB WDC WD1600JD-40GBB2
Mac OS X Leopard Version 10.5.8