Okay so currently my closest matching server would be my R730XD which is running dual E5-2650v4's which should have a similar power profile(the only diffrence with the 2680 is the number of cores however this shouldn't make much of a diffrence for low use workloads).
So currently with 2x SSD's, 2x2650v4's, 128GB RAM, 6x18TB HDD drives, 3x16TB HDD drives my power consumption sits around the 225-250W which over a month for me costs me about 50-75 euros a month in power(welcome to dutch power pricing...). However alot of this consumption comes from the drives, because before I put the HDD's in and just had the SSD's, the RAM and the CPU's it had an idle of around 80-100W. But this is in an enterprise server with some chonky drives so I assume those account for 5-15W as they have a base speed.
Generally I would say unless you specifically need functions that the board provides(alot of PCIE lanes for example) just get a consumer CPU and you'll be much better off as it will have better efficiency, performance and you'll be on a modern platform. And if you go for AM4 it will be really cheap cuz of the introduction of AM5.