Floor
Cables for power and data came into the boxes from below. Cooling air also came in there. The box had wheels and feet at the corners and expect a hole below them.
They were designed to stand on a floor, have cables come through the floor, and suck cool air in the bottom and exhaust it out the top.
One shop, the college before I worked there, had a basement, or crawl space I don’t know, below the machine roof and cut holes in the floor to route cables and cool air.
The vast majority, the college one was the exception from the over 100 shops I saw back then, were on raised floors. You took a normal industrial floor and put posts in a two by two food grid. On top of these posts you put two by two foot panels made of aluminum with something nice, usually vinyl, on top. These floors could be of different height, one height for one installation but different installations could have different heights. This gave you a nice, out of sight, place to run the horrible looking collection of cables. A plus was that you could set up an air conditioner on the side of the room and have it blow into the space under the floor to cool the equipment.
Under each piece of equipment you would cut a hole in the floor for cables and cool air. A brand new room might have lovely holes with edging to keep things looking nice, but soon you ended up with a bunch of strange cuts with raw aluminum edges. The holes were under the equipment and if they were at least kind of in the middle you could not see them. Those lively pictures of a clean machine room with clear floor around the machines was hiding a dark secret.
You occasionally had to get below the floor. Every shop had a floor puller. A suction cup with a handle on top and a trigger you could let air back in with. Stick this to a floor panel, pull up the panel, set it aside, pull the trigger to have the puller let it go, and on to the next. After you got one up you could keep going without the puller.
The only time I saw one of these panels break was when I dropped a box of paper from my shoulder and broke a corner off.
There were companies that did the floors. They would come in and lay out the grid, put a glop of adhesive down, and stick a support. They had to get this exact cause the floor panels went down with almost no gap. If you know mathematics, and real life, you know that four feet may not be level and the thing can rock. They would go around putting the panels down and checking for rocking. The height of a support could be changed and they would adjust it. It was not that simple cause if you brought one corner up it might ripple through the whole floor. They were good. I had a tile that was not level and I spent hours trying to fix it.
Cute story. The college built a new library and they put the machine room in the basement. There was a cutout and people could look through windows down on the machine room. The floor for the basement dipped where the machine was to go so, after the raised floor was installed it would all be level. To allow for future expansion the rooms next door also had a low floor and a raised floor. The machine room was locked when no one was there. One Saturday we came in and a guy was already in the room. He pried up a floor panel, that came out into the lobby and then ran into the expansion rooms, got in the space under the floor, went under the locked door, and came up in the machine room. I think he agreed not to mention it and the college ignored it.