CryoWolf :
I would say the the xeon is better for the rendering i.e Maya, 3ds Max in completing them quicker through the multi cores, but if you want to game as well I would take the i7 6800k as it has faster clock speeds and tends to cope better in them types of situations without bottlenecking. But the 6800k should make short work of 3d rendering too. I will have a look for some benchmarks for you.
Thank you Wolf.
I'm not interested in games for this rig, only rendering, but as you may notice, I have limited budget, so have to choose between CPUs like these two. In case 2620v4 have 2.8-3.0GHz clock speed, I wouldn't even consider 6800k, but with just 2.1GHZ speed, I was wondering, would 8/16 cores at 2,1GHz would be much faster than 6/12 cores at 3.6GHz. I know xeons are made for jobs like renderings, but still, in case of these two, I was completely confused.
I found some cinebench results I usually take as measurement for 3d rendering efficfency, but there are so many different results and I'm not sure which one to take as valid. Also, passmark and other benchmarks show not much difference between these two CPUs, so I wanted to see if there's anyone who had been in my situation and found a solution.
Rebusfarm benchmark result list shows that e52620v4 have cinebench r15 1831 multicpu score, but I found most of users have no more than 1200, also 6800k is not in base.
CPU-monkey shows cinebench r15 multicore score of 1096?! and one again 6800k is not in base.
Passmark shows 13500 for 6800k and 11870 for 2620v4
As you may notice, these informations doesn't help too much :/