Intel xeon "gaming" pc

tomshardware's forum is more specialized with computer discussion. I think you will get your answers there.

Why do you want a Xeon setup?
Either way, the turboboost frequency is what you want to pay attention to, at least 3ghz.

Xeons are designed to run dozens or hundreds of small to medium load processes simultaneously. A video game usually uses one to four threads with heavy loads. Therefore, Xeons at best will perform similarly to a Core CPU, but will cost more than twice as more. In many cases, they will run a game even worse, thanks to the lower clocks.

If you really want to blow a wad of cash on a gaming PC, get a socket LGA-2011 motherboard and put an i7-6950X in it.

last time i checked for those i couldn't even find cheap listings for great xeon cpu's [4 physical cores] (did look only a few times ...)
even worse the capable motherboards - those are the pricey hook to the cheap processors, unless you're right on time somehow

My current, 3 years old rig has a Xeon E3-1230v3, which is pretty much equal to a i7-3770 but was about 100€ cheaper at the time i.e. about the price of an i5. The main difference between the Xeon and the i7 is that the Xeon cannot be overclocked (non K model of the i7 cannot be overclocked either). E3-1230v5 seems to be the Skylake equivalent, but you can't get that for $150.

Definitely working. I just bought Dell T20 for 200€ few days ago:
Xeon E3-1225 v3
4 GB RAM
1 TB HDD

The power supply is pretty weak, with 290w.
So get another 150€ ready for a GTX 1050 TI, which runs perfectly with this system.

I already had 8 GB RAM from my previous system. An SSD is optional.

So 350€ for a gaming PC - best you can get for your money imho :)

I have got a HP z820 workstation on my work, (although I have tried running games on it as well) with 2 intel xeon cpu's a total of 32 cores each at 2,8ghz (for a total of 64 threads).
I certainly would't recommend intel xeons for gaming. Intel xeons usually have lower clock speeds (but more cores) than "regular" cpu's, they can not be overclocked, can get very toasty (need to be air or water cooled all the time), and are usually more expensive then i5 or i7 alternatives. Games usually are not optimized to use 32 cores with multi-threading. Most games will use only a couple of cores, hence making sure those cores have a high clock-speed is key to a good gaming experience. Most games rely mostly on the gpu. Some games might make good use of the cpu (city's skylines), but most games can run on sub-par cpus as long as the graphics card is good.
probably going to sell this workstation, as I am pretty sure I could downgrade to a less beefy machine and make a couple bucks. :)

If you want a good gaming pc invest your money in the gpu.