"HH" wrote in message
...
Back in the Pentium days, most Compaq motherboards were proprietary.

I have used a standard ATX in a Presario that predates PIII. You need to
check the I/O panel and the mounting screw holes and if everything lines up,
you must be certain that the new MB has the processor in a place that the
fan won't be in the way of the Power Supply. That was the only
consideration that I found.