I bought a brand new Zotac RTX 3080 AMP HOLO 10GB card, that’s not LHR.
I installed it into the rig without any problem, but can’t raise the memory clock above ~1350 Mhz, and can’t reach 100 Mhs.
I have same problem , i cant go more than 1350 and my hashrate exactly like you, if i go more i face whole system crashing, but in this number it is stable
my card is Asus Rog Strix Rtx 3080 non Lhr, i changed the bios and do a lot of things, even i dont have thermal issues, but it cant go more than 95 Mhs and 1350 Mhz memory clock