Pc not booting.

[Cringe123]

My pc randomly wouldn't boot today. It would just turn on then turn off again instantly and keep doing that over and over. I tried removing the ram until there was 1 left and then I swapped that for another stick and it still didnt work. The psu is still turning on and was working fine the day before. (80 plus gold). The graphics card is fine as it did the same thing on my intergrated graphics. I have no clue what it could be. Also after I replaced the ram for some reason it changed what it does on startup. Now it turns on then off instantly and then back on again in a few seconds and the fans keep ramping up for one second like it's trying it start and then they go back to normal. It repeats this every few seconds until turning off then turning back on again and doing the same thing. Nothing I have done worked. I even replaced the bios battery and it still wont work. System specs (rtx 3060, i5-8400, tx750m, 256 ssd, 1tb hdd, z370m D3H) Please help. I really need this pc to work. Thanks