As a temp solution until we have correct bios, try flashing this one. It is working with my vapor-x ghz, now more than 24h stable ~83-88 sol/s
ASUS R9 280X with HYNIX AFR memory
https://mega.nz/#!zwl1WDIa!kLFqZgCkMPiH1DOQe3Rg3FbQHpXZN-xq_CdmREBha04
Slight undervolt to 1.075V, 1070/1600.
MSI Might say 1375 for mem but its 1600 since I didn't update the previous DPM field in VBE.