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IBM still manufactures new mainframe computers and they will actually support your ancient mainframe from 1962 (assuming you’re still paying your licensing haha)
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the vast majority of Windows 7 and older computers that are still in production are attached to specialized hardware or industrial equipment. Stuff that costs many hundreds of thousands or millions of dollars.
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emulating older OSes doesn’t really solve the problem at all because the actual concern is security, not hardware issues.
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emulation isn’t perfect, especially with passthrough. Especially when you’re trying to pass through an ancient connector through a virtual adapter (show me a modern computer with SCSI)
I could keep going but that’s all I have enough care to do right now
This is some crazy good advice. In the software dev/IT fields I preach about premature optimization to my reports all the time.
You can’t optimize something that doesn’t exist. Figure out exactly what you want to build (so you want video streaming mostly it sounds like, then you can figure out how to build it (probably either a NAS or just a tower with a bunch of drives in it. And then Plex/Jellyfin). Then, after you build it, you can use it.
You’ll only find things to fix/make better by actually using it. Focus on getting the thing done, then you can optimize.