How can I find the speed of a powerbook 1400 in mhz what program do I need to use?

Try looking in the Apple System Profiler, if there is the program in the computer. Do a search. It's been a long time since I've used System 7 through OS 9, so I'm not too sure where it would be located. I think it's in the Apple Menu. If not, check the utilities part of the Hard Drive.

According to a basics spec program, MacTracker, the Powerbook 1400 had a "c" and a "cs" model. The possible speeds are 117MHz, 133MHz and 166MHz.

If the System Profiler cannot be found, or doesn't tell you, keep reading.

Most likely, if it's a Powerbook 1400c with a 1GB Hard Drive or less, it has a 117MHz processor. If it has 2GB from original, it is probably 166MHz.

Most likely, if it's a Powerbook 1400cs with a 750MB Hard Drive, it has a 117MHz processor. If it has a 1.3GB Hard Drive, it is a 166MHz processor.