How long can IDE cables be?

I have this idea of having the motherboard in a seperat case from the cdrom/psu/floppy, but to do this ill need to run cables quite a distance say 450cm, but im sure i read somewhere that IDE cables dont work after a certain length.

Any one know?

The maximum cable length according to the ATA standard is 18" (~50cm).

Ken

I was using nothing but 36" cables in my old server system... never had an issue

It may work, but cables longer than 18" and shorter than 10" will cause data corruption (of data traveling accross the cable). Because the ATA spec includes error-checking the controller chip will merely ask for the same data again, causing overall performance to drop. And the error checking is not perfect. Bad data may pass it, however that is unlikely and happens almost never with proper cables, but with really long or really short cables, because the data gets corrupted much more often, the chances that bad data will be read/written to the drive increase a lot.