[SOLVED] PC won't boot with the graphics card installed

[ElectricLute]

I've recently put together an almost entirely new PC with these specs:

CPU:AMD Ryzen 5 7600X
CPU cooler: Cooler Master 212 spectrum v3
Motherboard: ASrock B650M PG Lightning WiFi (bios version 3.06)
Ram: Silicon Power Value Gaming DDR5 32GB
SSD: Patriot Memory P400 Lite M.2 PCIe Gen 4 x4 2TB SSD
HDD: Western Digital Caviar Blue 1 TB 3.5" 7200 RPM Internal Hard Drive
GPU: ASUS dual gforce rtx 4070 super
PSU: corsair RM750 750 w 80+ Gold (~2 years old)
Chassis: Deepcool TESSERACT BF ATX Mid Tower Case
OS: Windows 11
Monitor: ASUS VS228

The only parts that have carried over are the PSU, case, and monitor

As long as the GPU is installed it won't boot, however it does boot with either no GPU or an old NVIDIA 1070 installed.
I have a hunch that the power supply is the problem because its the only part that's old, other than the stand-in GPU. But I'd like a second opinion before I go out and buy a new one, especially because I think it should be able to handle the load in theory.

 

[Lutfij]

Welcome to the forums, newcomer!

I've recently put together an almost entirely new PC with these specs:
When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.
+
what parts were carried over from an older system?

Moved thread from Systems section to Graphics cards section.

 

[ElectricLute]

Ive edited the original post with the requested info

 

[Hiddenpeanut]

This is from the ASUS website for your graphics card. I think it might be related to the connector cable not being properly seated but i'm a noob so.

Q7：If the graphics card output gets a black screen or abnormal screen during use, you can first check whether the LED light at the connection point of the power supply cable of the graphics card is constantly red or not?

A7：Please first make sure that the power supply cable of the graphics card is securely plugged in. If it is already plugged in, then check if the LED light at the connection point of the power supply cable of the graphics card is constantly red in operate system. If it is constantly red, you can try replacing the power connector cable and then recheck.

 

[ElectricLute]

I feel like an idiot.

Ive been using the wrong cables this entire time.
I suppose I should thank the GPU for protecting me from the consequences of my ignorance by not booting

let this be a warning to those that come after me. Make sure you're using the correct cables.

 

[JayGau]

By curiosity, how were you plugging it? I mean, there's only one connector on the card, how is it possible to use "a wrong cable"?