Another happy X58 user, lovely and welcome to the club
But you are seriously missing out a great performance boost with not overclock your CPU and if you are planning SLI with two GTX 1070 TI cards oc is a must to get the full out of two cards. These old chips goes above 4 Ghz with ease, just as long cooling is soficiant. A good air cooler can do it.
Basic your xeon is decoded to I7 models a I7 990X and i got a I7 980X so i know that chip has some OC potential. Got my own chip to 4.75 GHz (this oc is not the CPU's limit, but cooling cant keep up for higher) al throw i for daily use keeps it at 4.25 GHz. That makes it for a great gaming cpu (I runs games at 4K with my setup like BF1 at max settings and runs like a champ). My points is you shut really consider oc that CPU, even throw you had bad exsperience before. X58 is a solid platform that aint so easy to kill and the CPU's can go really high. Just make sure you keep temp in check and know the max safe voltages. I can comfirm that for sure. Got a I7 920 going to 4.4 GHz as well on air cooling. So i wont say i am a noob when it comes to X58 overclock.
Well no more talk. Time to show benchmark so you can se what potentials X58/xeon w3690 has. Al throw i cant say how well your asrock motherboard can oc, i have only worked with Asus X58 boards, but the chip it self has great potential.
First this is how my pc is running on a dayly basic.
then some Cinebench R15 runs at stock, 4.25 GHz and 4.75 Ghz.
Dont know if final fantasy is your thing, but here are some runs. CPU ran at 4.25 GHz on al runs. This is a new game to come next monfh and as you can se my system has no problems running it even at 4K resolution. Not to bad for a platform comming out 10 years a go.
A few 3dmark firestrike runs with my dayly clocks and max overclock.
And as a last thing a timespy run. Dit not get a screenshot of it, so only a link.
https://www.3dmark.com/spy/2333033