Oh man, msi board, x370 gaming plus. It boots, just not all the time.I set the HDD to UEFI and ahci is activated. The thing is that when it boots, everything works fine, but it boots like 30% of the times. I´m still in the same bios version that it came with. I know I have to update it, but its my home pc, and ill be home this weekend. I'm literally working on it a couple of hours just the weekends.
And what it does is that when I turn it on, the hdd and fans spin, but the monitor doesnt even get a signal, not even the keyboard turns on, just the mouse. I tried other keyboards, just in case and nothing. I have to press the on button for a couple of seconds to turn it off and try again. Processor is a ryzen 5 1600.