That's a meaningless worry. Each 8700K core is more than twice faster than a 5675 core. Therefore, in your case, if allocate 2 cores to each Windows VM, 1 core to the Debian VM, all VM will run faster on the 8700K Hackintosh than your current setup.
And 1 faster core can always finish 2 slower cores' job in the same period of time (assuming the speed ratio is 2:1). But 2 slower core, no necessary can do 1 faster core's job.
Also, the virtual CPU allocated to VM can usually can go up to ~5x total logic cores available without problem (but performance may be degraded of course). That means, for a 8700K, you can still allocate 4 cores to each Windows machine and 2 cores to the Debian indeed. That's just 10 virtual cores in total, not even able to fully utilise all 12 logical cores yet. So, the total physical core count is not a concern at all in the very beginning.
Therefore, in your case, running the same VMs on a 8700K Hackintosh with the same virtual core count (or half the virtual core count) only has benefit, but no disadvantage.
However, if you worry about resource, memory may be a bigger concern. Dual Xeon can go 128GB or even 160GB on the cMP, but a 8700k Hackintosh is limited to 64GB. If you really need more than 64GB in total for all the VMs, then 8700k Hackintosh is not even a potential candidate. But since you only has 24GB in total, that means the 8700K again can do better (because has faster memory).
Also, if you need ECC memory for your work / VM... Then 8700K Hackintosh also obviously cannot be a choice.
[doublepost=1535330921][/doublepost]Unless you insist to setup a VM that will completely "own" the virtual CPU cores (which is NOT the common practice because of low efficiency and flexibility. A more proper way to setup VM is only use the real CPU's power on demand). Then all you need to know is really just the how good the multi thread raw performance of that computer is. Core count doesn't really matter. In fact, depends on situation, less core counts may be better (for the same multi thread performance) as explained in my last post.
And This is what I can get form my 8700K Hackintosh. Which is faster than any cMP can do in both single and multi core situations. For VM, it's almost guarantee all VM can only run better on this computer than any cMP can do.
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