Secret BIOS Diagnostic codes

Does anyone know all the codes that can be used in the Dell BIOS. I know that while going through the POST if you press Ctrl + Alt + D you can run the HD diagnostics and while IN the BIOS Pressing Ctrl + Alt + E is supposed to clear the NVRAM. Are there any others. Come on you Dell heads and Dell support guys, spill the beans!

P.S. These work on the optiplex GX110 and, I believe, other optiplexes. They're really quite ingenious.