Comment by PunchyHamster

Hard to know at this point. In the past ARM sued people for daring to think about implementing ARM compatible computers. (Even university research projects.)

Of course, in the more distant past, AMD and Intel sued each other a lot. But there have been a dozen or so x86 market entrants. I think the competition has just been brutal.

So, with either one, you could, of course, do a clean-sheet design and hope you don't get sued.

Since ARM has historically only sold IP, they are incredibly jealous of their monopoly for that ISA. Of course, the flip side of it is that if you have enough money, and you beg and grovel enough, you can probably do what you want with their code.

Except, of course, when you can't. Or rather, maybe you can, but they will try really hard to stop you.

For example, Qualcomm, an architecture licensee who had purchased the rights to basically make whatever the fuck ARM they wanted, purchased a startup named Nuvia that also had an architecture license, and started using Nuvia's designs.

ARM sued, just because. They were shut down in court, but the message is clear. They are very aggressive.

Seriously, who needs that shit? Semiconductor market windows are tight enough as it is, and ARM has always acted like "Nice chip you've got there, buddy; shame if you haven't dotted your i's anc crossed your t's on the licensing."

At least with Intel or AMD, you're probably only looking at patent lawsuits, and you could probably do a decent job on a low end machine with techniques that were known 20 years ago.

You could do the same with ARM, of course, but they will sue you just because, to see if they can make you run out of money.