I've tried re-inserting the two 8 pin connectors and making sure everything is connected, but it will just not turn on. My PSU should be able to handle what I currently have installed, but maybe you guys know something I don't.
Specs:
Processor: (CPU) Intel® CoreTM i7 Quad Core Processor i7-7700k (4.2GHz) 8MB Cache
Motherboard: ASUS® PRIME Z270-P: ATX, LGA1151, USB 3.0, SATA 6GBs
Memory (RAM): 16GB Corsair VENGEANCE DDR4 3000MHz (2 x 8GB)
Graphics Card: ASUS GeForce RTX 3080 TUF V2 LHR - 10GB GDDR6X RAM - Grafikkort
SSD: 500GB Samsung 850 EVO 2.5" SSD, SATA 6Gb/s (upto 540MB/sR | 520MB/sW)
Hard Disk: 3TB SATA-III 3.5" HDD, 6GB/s, 7200RPM, 64MB CACHE
Power Supply: CORSAIR 750W TXm SERIESTM SEMI-MODULAR 80 PLUS® GOLD, ULTRA QUIET
Processor Cooling: Noctua NH-U14S Ultra Quiet Performance CPU Cooler
Extra Case Fans 1x 120mm Black Case Fan
Edit:
I found this video, that around the 13 minute mark explains that it may be because of the wiring, that it isn't able to feed enough power to the GPU. Could this be it?