How to Replace a CMOS Battery on IBM Personal Computer XT model year between 1980-87
It boot with ROM BASIC. its means no required Hard Disk or Floppy Disk for boot purposes..
Where is the location of CMOS Battery ? whether battery installed in power supply or motherboard ?
I'm remembering and reading on the internet, that the original PC and PC-XT lacked a CMOS battery, and adapters such as AST SixPak allowed customers to add a battery backed clock to their PC. I think the original PC and PC-XT required the customer to enter the date and time on every boot.
Thanks

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