Intel has a track record of changing sockets every couple CPU generations, so it might be a dead end as far as upgradability. At least with AMD AM5, we know that the next few Zen generations will use it.

I am inclined to stay with Intel especially since they seem to have caught up with AMD in recent releases.

Does anyone have any comparison statistics between Alder Lake and Raptor Lake CPU's as far as WCG is concerned?

Go with the 13700K. I presume an Intel Core i7-13700K. Or with an equivalent AMD. Not pushing either brand.

Two years ago when I started with WCG I had just junk computers. I started a thread here titled Raspberry Pi https://www.worldcommunitygrid.org/forums/wcg/viewpostinthread?post=637575

My reasoning for going with a Ryzen 3900x are just on the first two pages. My primary goal was actual work done.

My calculations showed me I would need 25+ Pi to match the 3900x. I use cpubenchmark to rate CPUs. Not that it's the Bible but just that ratings are all done the same. My 3900x rates 32749, your 13700K rates 47031, and the Pi, according to input from others, about like an old Core2 Duo CPU P8400 @ 2.26GHz which is 846.
https://www.worldcommunitygrid.org/forums/wcg/viewpostinthread?post=637651

I understand the concerns about electricity especially now in the EU, UK, and CH. It was not and is not for me because of where I live. (explained in the link) It's wrapped up here and the lesson learnt is the post after this one:
https://www.worldcommunitygrid.org/forums/wcg/viewpostinthread?post=658352

There are other comments on page 3.

Remember, a battery of Pi's requires stacking cases, wires, Sandisks, a switch or two, power strips, loading each one with the OS, monitoring once in a while, and maybe other logistics I can't thing of.

With a 13700K, one and done.

I've stopped keeping my stats now so can't give current numbers

I figured that out about the Raspberry Pi. I still have not given up on it and keep looking at the project ideas but still have not found anything I can get excited about.

Still though, if you have them lying around gathering dust then do let them crunch.

After writing this I went back to the Pi site and discovered a tutorial to allow network booting.which would make updating all the Pi's in the cluster stack(s) a bit easier. Had not seen that 2 years ago.

I had a old x99 (2011-3) system and recently checked the supported processors. To my surprise it supports Haswell (Xeon E5 xxxx v3) and Broadwell (Xeon E5 xxxx v4) server CPUs. The sweet spot to me seemed to be the E5 2697 V4 (18 C, 36 T) at about $85. The 20C and 22C were about $130, $250 IIRC. From my old processor I tripled the cores and cache, and got a node shrink from 22nm to 14nm. During 100% load its a little slower than what I could sustain on the other processor but it still hits 2.8 Ghz with all threads maxed out. Says 145W TDP but monitoring the package power it hasn't gone above 125W. Easy to cool with a simple tower cooler.

One thing you have to watch out for if going for a new build with 2011-3 is that some motherboards use narrow or square 2011-3 cooler mounting points so you would want to make sure your coolers supported whatever you were getting.

On the EPYC side I am waiting a couple years for the rome 7xx2 64 core processors to take a dip. Currently the 7B12 (64C/128T, 240W) are ~$925, so a dual socket system would still be around $3000.