Full build:
R5 3600, cooler from box
MSI MAG B550 Tomahawk
Corsair 16GB (2x8) Vengeance LPX DDR4 3200Mhz CL16
MSI Geforce RTX 2070Super Gaming X Trio
Corsair 650W RM650 80 Plus gold
I have checked cables again and again, reinstalled cpu and cooler once but MB debug detects problem with CPU. Do i have a reason to believe my CPU is broken or are there still some things to check before. I do not have another AM4 compatible mobo or CPU. Is there a way to confirm if MB is at fault and not CPU?
B550 has support for 3000 so it's not about bios either.
Is your Corsair RAM listed at MSI Support Motherboard QVL List?
Also check at Corsair and see if it is compatible with the Ryzen 3xxx series processors and your motherboard.
If it isn't then check if it is listed at AMD as being support: https://www.amd.com/en/products/ryzen-compatible-memory/ready-for-amd-ryzen
If it isn't listed in neither of the three lists then remove all the RAM except for one Stick of RAM and see if your computer will start.
Also try to boot up with the minimum amount of hardware connected to the Motherboard. (PSU, GPU, CPU, 1 Ram Stick, Keyboard and mice, Monitor).
Memory sticks are not on the lists provided but pcpartpicker lists this exact model to be compatible with my MB and Corsairs lists this exact stick to be compatible with Ryzen 2000 and 3000 series, also there are builds with these exact parts.
How ever i didn't realize to put mouse and keyboard on for test. On test CPU debug light is still on but neither keyboard or mouse has their lights lit on, on any port on MB or case. I don't know whether they should be powered up at this stage of starting pc up.
If you do not connect the CPU fan or the RAMs or the CPU 8PIN power cable in the right place, the system will not start.
Open your computer case cover and share a picture so all your hardware is visible.
You have made the necessary connections. If I were you, I would think the problem was with the motherboard and behave like that.