Which CPU is best for long time use Intel or AMD?

From second hand I pesonally would prefer Intel. AMD are usually less expensive when purchased new, but offer less safety features in regards of overheating, overclocking and other abuse. Intel's are guarded casual consumer products and I would assume there is more Intel out there, that has seen little use and should run sturdy for years to come. Buying second hand the chance the processor has been driven hard is maybe less likely for Intel. The advantage you have with AMD being cheaper shrinks in the second hand market. There is also just more Intel out there.

AMD traditionally offers more power for less money and you can also fiddle with it a lot. I destroyed multiple AMD processors. There are just more tools to mess with AMD and it is so much fun. They advanced a lot in reliability.

As others have pointed out, it is much more complicated.

What ice-cream flavor is best? Chocolate Chip or Strawberry?

Depends entirely on your goals.

If you want to minimize cost, it mostly depends on your energy cost. If it is low it doesn’t matter since all CPUs will gladly last 10 years or more. If it is high, go for the one with the least power usage overall (if 24/7 workload) or least idle power usage (if idling a lot).

If you want to put it in your bedroom you also want one with not so much heat output probably since it will be easier to cool = quieter.

If you need to do processing or Virtualization you want multiple cores. If you do IO intensive tasks you need lots of PCIe and probably high clock speeds … etc etc

So what are you trying to optimize for?

At this point if you find a good Ryzen 3x or 5x series would be my recommendation. IMO AMD nailed it and they are ahead of Intel. Until Intel comes up with a new design it will be hard to keep up except to increase Clock and add minor features.

What does that mean? 24/7, or which ones still keep up well 10 years after they were released? It depends what you want to do with it. Decide what specs are important, look at some benchmark comparisons, browse ebay.

No.

ARM or RISC-V.

Apple makes some very nice ARM machines. If you’re running Windows, see https://support.microsoft.com/en-us/windows/windows-arm-base...

Read Hennessy & Patterson and get back to us.

They are the same these days