Strange booting problem

[Gordon Messmer]

On 06/25/2015 03:55 PM, jd1008 wrote:
> OK, but since this drive is my only backup drive, I feel
> I cannot run dd to clobber those 466 bytes :(
> Too risky, even if I feel nothing can go wrong, but ...
> murphy's law ....
>
> Re: sda1: here is the output:
>
> dd if=/dev/sda bs=2 count=1 skip=255 2>/dev/null | od -x
> 0000000 aa55

Sure, caution is warranted.  Setting your BIOS to boot HDD first, and 
using F12 when you need USB boot is a perfectly reasonable solution.

My point is merely that there's nothing wrong with your BIOS.