legenda-

I did that for like 2-3 times at my mobo, i even changed the cpu and the mainboard 3 times and it still won't boot up. I've changed my motherboard to a b450m-m2 from MSI and I noticed that the LED won't blink or light when I start the PC

But it worked fine before? I tried, still no changes

Hello, first of all I'm sorry for my broken english, I'm from Austria. Last week I built a new gaming pc, everything was working fine, till I noticed that my CPU is running at 70°C in idle, so turned off the computer and opened my case, and noticed that my cooler isn't screwed in right. So I took the cooler out and screwed in, in the right way. I started my PC and noticed it the PC wasn't booting anymore, since then it won't show any signal, or even the GIGABYTE logo of the mainboard. The fans and everything else are working, but the PC won't boot up and my keyboard & mouse which have LEDs don't light up, so the USB ports isn't working too. I've tried to boot up with a GT 230 and the PC worked fine, so I tested the GPU in a other system, and it worked fine. The GPU was working fine, so I thought it's because of my power supply. I tried it in a other computer and it worked fine too. Since then my PC won't boot up with the GTX 960, but it boots with the GT 230. My Ryzen 3 1200 hasn't any integrated graphics, so I can't boot up into Windows. What I have tried out: - reseting BIOS - updating BIOS - re-plug in and out my PC - changing the RAM stick in a different slot - sending back my mobo and get a new one, still same problem - changing the hard disk my rig: CPU: AMD Ryzen 3 1200 (4x 3.1 GHz) GPU: MSI NVIDIA GeForce GTX 960 OC 4GB RAM: Crucial 8GB DDR4 2133MHz PSU: Thermaltake Smart RGB 500W HDD: 500GB Motherboard: GIGABYTE GA-A320M-S2H