5.25" CDROM Mechanical Information

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Looking at a "random sampling" of 3.25" CD-ROM drives, it looks like they
all conform (more or less) to some kind of mechanical standard, de-facto or
otherwise.  Is there an actual specification for this -- outer dimensions,
hole locations, connector locations, etc -- or did everybody in this
business "just know" what to do?  Any information would be greatly
appreciated, ESPECIALLY URL's for drawings of any kind.




Re: 5.25" CDROM Mechanical Information

Quoted text here. Click to load it

   I assume 3.25 is a mistype, and you meant 5.25, as in the subject.

Quoted text here. Click to load it

   I bet they're the same mounting screw locations as on 5 1/4-inch
"half-height" format hard and floppy disk drives (who remembers
"full-height" 5 1/4" floppy and hard drives, as used on the Apple ][
and IBM PC and XT?). The half-height "standard" probably goes back
well over 20 years, and "full-height" even further.

-----
http://mindspring.com/~benbradley

Re: 5.25" CDROM Mechanical Information
Quoted text here. Click to load it

It's actually a superset of the old standards for 5.25" floppy and
hard drives. The outline is the same as for a hard drive, but the
screw holes are more numerous. If you want to be as safe as possible,
you should use the side-entry holes, and make sure you have screw
holes for both sets (upper and lower).

Connector position is not fully standardized, but any drive you buy
today is 95% likely to have the power connector on the RH side
(looking at the drive from behind) and pin 1 of the IDE connector next
to the power connector. This de facto standard seems to have arisen
from the people who make the all-in-one connector+jumper assemblies,
rather than the other way round.

The reason I stipulated 5.25" CD-ROMs is that although they are not
100% identical in size, they are DARN close to it. Laptop CD-ROMs,
though much sexier, are (a) more expensive, and (b) considerably less
standardized. (Bitter experience speaking there).

Re: 5.25" CDROM Mechanical Information
Quoted text here. Click to load it

There's a spec from the SFF (Small Form Factor) committe.  I don't have
more info at hand.

Site Timeline