you got a block on your nb or you using the heastpipe+ block

i ran nb 1.63v watercooled forever n my nb never hit 35c
as long as your temps are good ....
its heat that degrades the nb n goin over 1,7v
i also have enzotech copper heatinks on pwm

i doubt you gonna hit 1900mhz
its tough hittin 2000mhz with 2x2 lol n you wanna do 4x2b with a quad