Custom Gaming PC just stopped working

Hi all! I am completely out of options and at a total loss for answers/solutions so I am taking to the community to see if anyone can provide help with my issue.

Computer Specs:
-MSI X99 SLI Plus MB
-Intel Core I7 CPU
-Corsair H100I liquid cooling unit
-EVGA Supernova 850G PSU
-128gb SSD (Operating System Installed here)
-1tb WD HDD (All other files)

So with this PC, Cyberpower PC made it about 3 years ago(It is outside warranty). The PC always went into sleep mode even when i turned it off in windows, which the cyberpower pc rep advised me that this was normal since my system did not take up alot of power when idle running. Now I work on basic business PC's at work all of the time and I replace parts in PC's daily which all result in fixes. With that being said, I left my PC in perfectly working condition one night and came back to it an hour later and it had gone into sleep mode which always happens, usually i just start it back up and it works perfectly fine. This time it came back on fully but showed no display at all so everything in the pc was running as normal but i was getting no display. I have tried different power outlets, Different monitors, Bought a new power supply and that did not change the outcome. I have removed ALL components other than the motherboard,cpu,power supply and still same issue. I have sent my motherboard back to MSI and they replaced it and sent me a new one. I put replaced that in the system and still the same issue. I have no idea what the issue is at all. I cannot get this PC to even post/get into bios. Please anyone that can help me I would be grateful! I cannot afford to buy another pc or start replacing parts as they are not cheap.