the boot time is < 15 seconds for the OS
it is the BIOS POST that takes 17 seconds..
That I couldn't explain D:, the problem with finding our what's causing it is annoying in itself. It could be your cpu, a ram stick or the mobo. The first thing I would do is make a memtest disc and test your ram sticks individually.
Could just be looking for something that isnt there, perhaps the lan boot is in the boot sequence.