Every time I hop in a game, doesn't matter the stress load, my pc crashes to a green screen with no error codes. My motherboard has error lights and the CPU one is the one that lights up whenever it happens. It doesn't crash when downloading a game or just sitting in the web browser or at the home screen. It worked for about a week or two then this problem appeared.
CPU: 2700x stock cooler
GPU: RX 5500 XT
PSU: corsair CX750M
Ram: T-force Xcalibur 8 g x2
Motherboard: MSI B450M gaming plus
It could be a faulty processor or more than likely it could be issues with your ram timings. I've been there & done that, once you get it stable, you're significantly less likely to crash.