No, in the case of a hard disk it is not much about the tool used, but rather on HOW it was partitioned/formatted.
If you prefer, before and outside using the nt6x fast installer (or - advised - it's evolution: http://www.msfn.org/...inntsetup-v372/ ) one should make sure that the disk is bootable.
There are several possible hiccups in doing this sometimes also due to the particular combination of the way the hard disk is partitioned (and the CODE used in MBR and VBR) with the particular BIOS and even in some rare cases with the actual controller in the USB enclosure.
A "complete" answer to the "HOW EXACTLY" question would be something like:
I used tool x under Operating System y to make:
- a MBR (or GPT) disk, with
- a single primary partition, formatted it as (NTFS/FAT16/FAT32/exFAT etc.) and
- made it Active
- the partition is Mb (or Cylinder) aligned, and starts at offset xyz, and extends for xyz sectors
- the MBR code is the one from xyz (example Standard XP or Standard Windows 7 or grub4dos or Syslinux, etc.)
- the PBR code is the one from xyz (example Standard XP or Standard Windows 7 or grub4dos or Syslinux, etc.)
The "No bootable device - insert boot disk and press any key" is likely to come from your BIOS that *somehow* does not consider the disk as a bootable device, it may be connected to the BIOS itself (BTW which make/model is your PC?) but nowadays it is rare to find a machine that cannot boot from USB, so it is more likely that something in the partitioning/formatting is missing or "not suitable".
You could make a copy of the MBR of the USB disk using (say) HDhacker (you want to get first sector of PhysicalDrive):
compress it in a .zip file, upload it on *any* free hosting site and post a link to the .zip archive, so that I can have a look at it.