Laptop Harddrives

[Jon Pruente]

Yep, I've heard both Compaq and Dell have used ATX plugs with
non-standard pinouts.  As for HDD some makers put a very basic BIOS on
the mobo and the rest on a special partition of the HDD.  Usually you
can find a floppy that will create it on a new HDD, but it's a pain. 
I haven't heard of any thing much past early P1s that did this, so
anything using a 4GB+ HDD stock is probably safe.