Sorry for bad english but bear with me
Mobo:asus tuf gaming b450m-plus ii
Cpu:ryzen 5 2600
Ram:crucial Ballistix tactical tracer 3000hz ddr4 16gb
I had my cpu and ram for months just bought this mobo from used market , the previous owner sent me a video ( see screenshot ) of it working went to bios showed me the same date of my conversation with him and the components so i suppose it's working.I put everything together and boom black screen , got it to two repair centres tested it with other gpu and power supply but they didnt have any ryzen spare parts only could swap rams with another system so my ram is working fine, other ram didn't solve the issue , they both told me my cpu is working since mobo gives beep sound after removing ram, told previous mobo owner about the problem he insists the mobo is 10/10 and had been working with him since day 1 till the day i bought it, he said he didnt mess with anything or even dismantled his system since he built it and only he updated the mobo bios to ver 2807 with a flash drive . I can't seem to find the cause of this problem and the bigger repair centres with spare parts in my country are only in the capital so not an easy way to go , would really appreciate if you guys help me .