thinking of the "ultimate" retro x86 PCs - what bits to seek/keep ?

[Chuck Guzis]

On 06/06/2016 08:28 AM, Liam Proven wrote:

> AIUI -- not sure -- the 720 kB *format* was mostly used on 5.25"
> DS/DD 80-track disks, no?

I'm not sure what you consider 720K, so the question is hard to answer.
 On MS-DOS machines?  Perhaps, but there weren't a lot of them in
comparison to the IBM PC and its ilk.

But IBM offered the "slimline" 3.5" drive pretty early on; see the O&A
section on it--and it was indeed a DD "720K" formatted application.

(FWIW, the earliest drives on the 5150 were used as 160K and 320K format
implementors.)

>> If a good 150RPM ED drive were to have been readily available, then
>> 2.8M could have been retrofitted to all 1.4M systems, including
>> Amiga, etc. But would that, and the Barium-Ferrite disks have been
>> worth it for just twice the capacity?
> 
> Wouldn't they have got much cheaper if every cloner had used them?

Slow-spinning floppy drives are at best, a kludge.  Like a lot of other
physical phenomena, the energy induced in a read/write head is roughly
proportional to rotation speed.  Low speed -> low output.  So not such a
good idea.  I liked the idea of the 600 RPM 3.5" Sony drives.

--Chuck