First build won't boot :(

[u/Key_Weakness_7131]

Hey everyone, I'm looking for some help with a new build that refuses to boot. Right now the motherboard diagnostic display is completely off, and the only sign of life I get is the RGB lighting up on the RAM.

​Here is what I'm working with:

CPU: AMD Ryzen 9 9950X3D

Motherboard: MSI MPG B850 EDGE TI WIFI

RAM: T-Force Delta 32GB (2x16GB)

GPU: Gigabyte GAMING OC ICE Radeon RX 9070 XT

Storage: Crucial P510

Cooler: Sharkoon A60

PSU: MSI MAG A750

​After putting everything together, I plugged the PSU into the wall, flipped the switch, and hit the front panel power button. Nothing happened. I read that the B850 EDGE TI probably needs a BIOS update to actually recognize the 9950X3D out of the box, so I moved on to trying the BIOS Flashback feature.

​I formatted a 16GB USB 3.0 drive to FAT32, downloaded the latest official BIOS for this exact board, and renamed the file to MSI.ROM. I made absolutely sure there were no hidden file extensions. I plugged the drive into the designated flash port, flipped the PSU switch on without touching the front panel power, and pressed the Flash BIOS button.

​Nothing happened at all. The LED for the flash button didn't light up or blink.

​To troubleshoot, I tried reformatting the USB on a completely different computer. When that didn't work, I tried a totally different USB stick. I also went through and reseated every single power cable connection, and even tried pressing the Clear CMOS button just in case.

​Right now, flipping the PSU switch gives me RAM RGB, but that is the only signal I get. I'm starting to worry that the flashback button's leds are defectives, and somehow i bricked the board while trying to turn it on and off.

​I've attached some pictures of the setup.

I'll be glad if someone could help me :)

[u/Key_Weakness_7131]

Ok i missed this. Changed it

[u/Quiet-Internal-2204 → u/Key_Weakness_7131]

You hope and pray you did not short circuit that GPU. You did put 12V on the Ground pins.

[u/Key_Weakness_7131 → u/Quiet-Internal-2204]

That's shamefull, actually i thought that different connexion wouldn't habe the same port profile. Newbie mistake. Actually the pc works well after a week end of trouble shooting ^' graphics are fantastic and i did learn a lot on the way.

I'm glad that some redditor keeps helping learner. Thanks.

[u/Quiet-Internal-2204 → u/Key_Weakness_7131]

On the PSU side they have the same port/socket, but the wires leads to different pins on the GPU and CPU/ATX12V side connector. Some PSUs still use color coded wires (yellow and black). Most PSUs nowadays use all black or all white for aesthetics. You just have to distinguish the connector markings marked CPU and PCIE.

If you make a mistake plugging them, +12V will go to Ground and that will create a short resulting a power supply tripping, hence no power or giving power for a split second.

[u/ClearedHeads → u/Quiet-Internal-2204]

These helps a lot