Per Intel spec the ram is supposed to run at 1.65v in x58, and if you're using 1.5v ram then it's not actually designed for x58 systems. You can sometimes get 1.5v ram to work in x58 @ 1.5v but that's not how it's "supposed" to work so it's totally "your mileage may vary" and (according to cpu-z at least) it says you're using single channel, that's probably why it works at all, usually in all my past experience overclocking x58 for years I never could get any ram to work in x58 @ triple channel with 1.5v in multiple systems. Maybe it'll work for you. Maybe I was unlucky.
I see you have 2 sticks of ram, you may want to refer to the manual for your board for how to populate the ram correctly for dual channel. At least make sure you're getting the most out of the ram you already have. Triple channel ram kits are really cheap today online if you look around.
You will probably have better luck with a 1.65v-designed kit.
Also your scores in cinebench would improve a good bit with triple channel. The memory performance in x58 is severely crippled with single or dual channel configuration.
I also wanted to share this: https://ark.intel.com/products/47922...-GTs-Intel-QPI
You can go all the way up to 1.350v v-core with that chip per the intel spec and you aren't even exceeding the rated voltage for that chip.
You're using the revised 32nm Westmere core chip there, with the improved memory controller compared to the 1st generation x58 chips based on Bloomfield. The 32nm x58 chips should be good for at least 2400 mhz ram @ 1.65v @ triple channel. I had a 32nm i7-980x that ran @ 2400-triple-1.65v for 5 years daily at one point.
If you can manage cooling don't be afraid to push Intel x58 chips hard, I ran my x58 980x chip @ 1.575v @ 4.8 ghz @ average load temps video converting in the 90's C that way for 5 years. It still worked when I sold it in 2016 to a friend, and he's still using it to this day daily @ 4.8 @ 1.575v just like I had it. He games in guild wars 2 daily on it like that, still works fine, I haven't heard him having any issues yet. These chips can handle way more than most people seem to think they can. Remember, x58 series of chips had soldered IHS, just like sandy bridge. They're not as fragile as modern chips are.
It's nice to see someone making another x58 build in 2018. I always loved x58 myself. The only reason I don't still have one is I moved on to 1080 Ti for my modern-gaming computer, and x58 (no matter how high you overclock it) is a serious bottleneck for any modern card. Need at least 2014 or newer system to pair with a 1080 Ti to get the most out of it.
As long as you're sticking to GTX-760, or even dual 760's, or other older cards you'll be fine.