HP DL380 G6 Boot Issues

[Not-Zero-Blank]

Hello, everyone!
I got an old HP DL380 G6 server from work, but I'm currently having problems with it. The server does not start the operating system. I've tried everything. I double checked the boot controller, I also tried a PCIE SAS controller which also doesn't boot from, I used an M2 SSD PCIE card to boot from which didn't work either. I even tried the sata port from the cd/dvd drive with an external power supply...the raid configuration is ok too. It booted once when I wasn't looking. I can't explain why it suddenly booted. Also, I was in the diagnostics menu and ran the Boot Disk Test, which passed successfully. Im still hoping to fix it, since its a Pretty good Server for a Student.
Thanks in Advance

Sorry for my Bad english -.-

[support_s]

System recommended content:

1. HP ProLiant DL380 G6 Server - ROM (P62) Release Notes

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[BPSingh]

Greetings!

What is the Storage controller installed in the server? 
And how many drives and what RAID?
Do you see any error on the POST screen?
Last time when the server booted, what was the configuration?
What is the LED indication at the front and rear of the server?

https://support.hpe.com/hpesc/public/docDisplay?cc=uy&docId=emr_na-a00020562en_us&lang=es-uy