I have a Packard Bell (looks to be mechanical keyboard that has arrows on the back for XT or AT. The arrows point left or right depending on which you want. In between the arrors is what looks like a button, but if you push it in, it just goes into the hole and does nothing. I took the keyboard apart and there is nothing underneath where the button would push into.The keyboards circuit board is about 3/4 inch past the end of the hole but there is nothing there to be depressed, and the small push button had nothing behind it anyway, its just a round 1/8 inch think plastic circle you can push all the way into the hole....
Is something missing on the back of the keyboard? Not sure how to switch fro XT to AT or what is supposed to be there
The keyboard is from an old Packard Bell PB500 PC Clone