Noob here! I have just started building my first mining rig. I was able to flash all of the BIOS on my 3 RX 580 8 Gb GPU's, but after 10-15 minutes, the hashrate drops from 28.5 Mh/s down to 20 Mh/s per card. After awhile, it will go back to 28.5 Mh/s and hold steady, but then drop again.
Could this be cpu throttling, temp throttling, or unstable vbios???
GPU's = 6 x AMD RX 580 GTR 8GB OC+ from Best Buy PSU = 1000 W and 650 W CPU = Intel Celeron G3930 7th Gen mobo = Biostar TB-250 BTC 4 Gb DDR4 Ram 60 Gb SSD