Dell Optiplex 170L no Bios Boot from USB

SOURCE: Optiplex Gx110 Freezing on Bios Post

The only thing I can think of is there should be a jumper pin that on the mother board that resets the cmos. Unplugging the battery does not clear the cmos rom. My guess would be the cmos rom is currupted and unfortunatly you need the rom loaded before you can flash and replace it. My advice is ditch it.

SOURCE: Dell Optiplex GX260 desktop-how to reset factory settings in BIOS

sir try to remove the pill battery its in the inside of ur box that return it that might give an error said that u shud configure again ur time and date but that is easy but taht will increase teh speed and gives a reset to full factory defaults

SOURCE: dell optiplex 170L hard drive recognition

Ms Driver gets flaky sometimes. Get New driver from Dell Downloads.
Contact Dell Support for more INFO

SOURCE: Dell Optiplex 170L does not recognise an 80GB Hard Drive

Just for giggles try changing the boot order so that the C drive is first

SOURCE: my dell optiplex gx200 bios can't boot

maybe try taking out the cmos battery located in your case, looks like a small watch battery, that will clear bios settings and start from scratch, if there is no battery then there is a jumper sequence to do this