Use a modern PSU to have a 12v and at least 10A is possible ? : r/buildapc
Main Power Supply Connector (20-pin)
HIGH POWER ® Accesories - 20-24 pin Adapter (Motherboard Stablizer Cable)
Computer PC Internal Power Cable 4.2mm 20-pin to 24-pin ATX Power Supply Adapter | eBay
20 Pin to 20 Pin ATX Extension
How to connect a 20 Pin PSU to a 24 Pin Motherboard! - YouTube
ATX 24-pin Power Supply Connector with 20-pin Board & Visa Versa
Power Supply Reference | GeGeek
Trjgtas Dual PSU Power Supply 24-Pin ATX Motherboard Splitter Cable,24Pin(20+4) for ATX Motherboard Extension Cable - Walmart.com
Computer Power Supplies - iFixit
Safest option in adapting PC to support GPU 1070ti [PSU pin connector missmatch] | Tom's Hardware Forum
J.D.Research, Inc. 20pin-to-24pin Adapter
PC power supply cables and connectors
ATX power: 20 or 24 pins? - Super User
PC 20/24 pin 4/6/8 pin ATX SATA HDD Floppy LED LCD Power Supply Voltage Tester | eBay
Amazon.com: 24PIN Power Cable,Large 24 Pin to Small 24 Pin Power Supply ATX Adapter Cable,ATX 20-Pin to Mini 24-Pin Power Converter Adapter,Plug and Play for HP Computer PC : Electronics