well,the same as me, boot 3015mhz 1.8 and 1.87 in windows and 3151mhz but for me this is the imc limit, but my cpu was under ln2 and it shows your imc is more better than mine, I think your memories can do 3200 without drama
my cpu gave me 00 when i boot with under 105 BCLK @ colder than -80, so i booted windows at -80 and in windows i made it cold to -140 and start to set bclk in windows, colder imc gives me 20Mhz more vs -80Temp