HELP PLS - upgraded stock psu fan with Noctua NF-A6x25. Soldered black to black and yellow to red and crimped into 2 pin. As far as I'm aware I've not done anything
TWO Noctua NA-YC1 Y Cable Splitters Black 2 PWM Fans to 1 Header 4-pin adapters | eBay
Noctua NA-SYC1, 4 Pin Y-Cables for PC Fans (Black) : Electronics
Noctua Premium Fan Review: Closer Look - Cables - Noctua NF-A Fan Series Features Roundup - Page 4
NF-A4x10 FLX
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NF-A4x10 FLX
Amazon.com: Noctua NA-SYC2, 3 Pin Y-Cables for PC Fans (Black) : Electronics