HSC English First Paper Model Question

9.4. Power Supply Connections

On the side of the power supply is the on/off switch for the computer. Sprouting out of the other side are the power connectors. 

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Most power supplies have two connectors that are sometimes labeled P8 and P9 that connect to the motherboard; other nonstandard power supplies use a single connector. Looking at P8 connected to P9, you might wonder just why IBM designed a power supply interface to the motherboard that can so easily cause troubles; after all, if you reverse P8 and P9, as some of my friends have done in the past, then you irreparably smoke the motherboard. Why didn’t IBM use a single larger connector? Oddly enough, IBM did; the first prototype PC-which never saw production had a single large connector from the power supply to the motherboard. But, in the final days of setting up the new microcomputer for production, the company supplying the connectors went out of business, and the only way to not get behind was to just use two connectors that were readily available from another vendor. Since then, some other companies have gone to a single-connector design, but that hasn’t become part of the de facto PC standard, sadly Power supplies also sport from two to four identical Molex connectors for attaching to drives (hard disks, floppy disks, and tape drives), and most modern power supplies also include the smaller Berg connectors used to power 3.5-inch floppy drives. The motherboard receives power through the power strip in the northeastern corner of the board. (This assumes that you are looking at the board so that the memory chips are closest to you and the expansion connectors and the keyboard connector are farthest from you.)