The most important maintenance step you can take is to "ghost" or image your hard drive. Having a spare, pre-imaged IDE or SSD drive allows you to recover from a crash in minutes rather than weeks.
If there is one "exclusive" tip that saves more Mazatrol 640M systems than any other, it is proactive battery management. Unlike newer systems that might give generous warnings, the 640M relies heavily on its CMOS battery to retain parameters and tool data. mazatrol 640m maintenance manual exclusive
Use the RS-232 port or the floppy/PCMCIA slot to backup all machine parameters. The most important maintenance step you can take