I've built a number of both Intel and AMD models; usually building two to three models a week.

For long term crunching and remaining on as long as possible or as much as possible...

Would suggest Intel over AMD. Start off with as good of a motherboard as one wants to afford. Try to get an Intel i7 chip or possibly an Intel i9. You will only need 16gb or ram, and preferably any SSD 64gb or larger. Anything left over, any graphics card should do for light gaming - even intermediate level gaming.

Why ?
My WCG experience is rely on the last 10 years with AMD CPU and 13 years with Intel CPU.

• AMD
  
  
  • 2x Athlon II x4 (600) - about 9 years operation, replaced 1 year ago with the Ryzen 7 2700X, very reasonable electricity consumption
    
  • 2x Phenom II x6 (1055T, 1090T) - 10 years, still in operation and well running, reasonable electricity consumption
    
  • 2x Ryzen 7 2700X - 1+ year operation, excellent performance and at the same time, really affordable
  
  
• Intel
  
  
  • Pentium P4 - about 4 years operation, very poor performance and high electricity consumption, died, even clean and well ventilated
    
  • Q6600 - about 6 years operation, good performance, died, even clean and well ventilated, relatively high electricity consumption comparing to the performance
    
  • Q9450 - about 5 years operation, good performance, died, even clean and well ventilated, relatively high electricity consumption comparing to the performance
    
  • Xeon 5345 - died after 4 years operation, Intel server board with double CPU config, good performance, very expensive, died, even clean and well ventilated, disappointing short life, the Intel mother board has problem.
    
  • i7 4770K - about 7 years, still in operation, good performance, expensive comparing to AMD CPU
    
  • i7 6700K - about 4 years, still in operation, good performance, expensive comparing to AMD CPU

Conclusion
Based on the CPUs I used, AMD CPUs were more robust, more affordable for good performance and remain well performing over the years. Beside all these aspects, AMD is very fair with its customers, since the CPU socket is really stable over the years. With an AM4 socket, it is still possible to update the CPU without to have to change the mother board.
From this perspective, Intel is very frustrating.

Cheers,
Yves
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Disclaimer: I do not have any interests neither by AMD nor by Intel.

It is just an experience report.
I am only surprised to have to notice, that several Intel machines died relatively early comparing to my expectations and to the AMD machines.
I usually use Asus main boards only excepted the Xeon machine with an Intel main board and the P4 machine with a Gigabyte main board.
Yves

I must be very very lucky then. I have machines currently running that were manufactured in 2009, both Intel and AMD, running 100%, 24/7/365 in a room at a constant ambient 78F (25.5C). Never replaced a power supply, motherboard, processor, memory dimm, anything. Did have one disk go bad but since it was in a RAID 1 array and in a server, just pulled out the disk and replaced with a spare and off it went. Didn't even have to bring the server down. The disk manufacture date was 2009, so original equipment. I'm constantly amazed at the life span of the fans and disk drives as they have been spinning constantly since 2009. The bearings are amazing....Maybe the difference is these are enterprise grade equipment not consumer grade....

I had shut down the Q6600, for while just because I know it is inefficient, but put it back on line for Open Pandemics. I do have one I7-3770 running now and I am happy with it. The Q6600 is just a sentimental favorite because my son bought if for me on my birthday many years ago. It was a good upgrade from the Core 2 Duo I was using at the time. When I find a deal on a more current machine, I will put it out to pasture (from crunching) once again.
I appreciate your advice.
Cheers