Nemorino Hi,please send us a picture of SN on the bottom of the PC. May I know what’s the version had you updated for the machine?
Here are some solutions you could try:
①Please change another HDMI cable or power supply.
②Please take out the RAM ,please clean the contacts of the RAM with a rubber. Here is the tutorial https://url.bee-link.cn/AzzB or https://mega.nz/file/7nwDmCaL#UyzSmVkqJG8HW9dhjHhLkkzdP9gt2Br3xyCG1SCdbrA
③ Please take out one RAM and leave the other one in it to test if the RAM is defective or not. When testing, please turn on the PC, and wait about one minute, if you can go to the system, Please repeatedly press delete key as soon as your restart the PC, go to BIOS. Go to Boot option, enable fast boot, press F4 to save.
④Please check if the fan spins?
⑤Please tell us if the Keyboard light is on ?(Very important). If the keyboard light is on, it should go to the system, we need to troubleshoot HDMI or the monitor.