To overclock or not?

[FastGame]

I get errors with prime95 after a couple of minutes

I guess if you can operate your PC without problems in your daily activities you could say everything is stable, that being said the truth is if Prime95 crashes then something isn't right.

running the cpu vcore at 2.7v and mem at 1.7v

You have those reversed ? should be CPU 1.7 and mem 2.7.

You could raise the V-core 1.75/maybe 1.8, I wouldn't raise the mem more than 2.8. I had that same ram with my A7N8X-D and it wouldn't OC high nor did it like high voltage.

I have no clue why your PC doesn't boot with a lower than 11 multiplier, did you try all the lowers ? 9/10/10.5 ?

Did you try different memory slots ?