That's a different story if you don't have an OS installed. That would explain the error. Make sure that you have an OS installed and if the install...
BIOS (basic input/output system) = BFD. https://support.hp.com/us-en/document/ish_3912651-2318005-16 You indicated a previous issue with the system....
It sounds like it can't find the hard drive. I suspect either a problem with the drive or a problem with the mobo. What was it doing before? Have you...
2nd ASUS X299 Apex/Intel i9-9940x with Custom water loop/7H-Prem-x64/Corsair 450D case/Ram Trident-z 3600C16 4x8gb / Samsung970Evo plus 500gb SSD/Dual ssd EZ swap evo/PSU EVGA SuperNova 1200w-P2 80+Platinum/GPU Titan Xp /8-ML-140 on push-pull on 2-280GTX rads