dps-1200 + atx =
1st boot 435 W -- crashed on 2nd remote login
2nd boot 539 W


Only
First boot 427 W - reboot
Second boot 431 W

HWiNFO64:
CPU: 23 W
VEga 100W
1080 Ti 160W


I'd say its most likely power supply line quality and this chinese mobo not mixng very well.