Hi,
The optiplex 780, the drive from the other 780 is dated from April 2007, I imagine it was never used when Windows 7 was installed on it back in November 2015.
As for the other systems, I'd need to view them again. But the GX270 drive which is over fifteen years, has a low usage. I don't know if the drive was the original or not, the system has two bad capacitors could be a third soon, but other than a temporary Linux system, it is pretty useless to use. I was editing a map level on it, for an old game, but the person helping me didn't want to assist me anything with it.