Question PC won’t power up when CPU-PWR1 is plugged in

[Aaranga]

Just installed brand new mobo and cpu. After plugging everything in and turning it on, the mobo would flash its LEDS for a split second & that’s when I saw the “EZ Debug LEDs” indicate CPU not detected or fail. After removing cpu fan and seeing all the CPUs pins intact, I reinstalled and tried to boot up again (while leaving the CPU-PWR1 unplugged) and the PC turned on. I pressed the power button to turn off but it wouldn’t until i flipped the switch on the PSU. As soon as I plug in CPU-PWR 1 the PC would cut off with no power.

Saw a post with a similar problem but his fix was pushing the connector to the CPU-PWR1 all the way in. I’ve tried that with no luck. Any ideas?

Motherboard: MSi B450 TOMAHAWK
CPU: AMD Ryzen 5 3400g
Power Supply: Smart Series 700W
Graphics: GeForce GTX 1060 6g

 

[Phaaze88]

It's the regular Tomahawk, and not the Tomahawk MAX? The former has older bioses that don't recognize the 3400G.
You need to download a newer bios from the product support page and make use of the board's USB Bios Flashback:

View: https://www.youtube.com/watch?v=iTkXunUAriE

 

[Aaranga]

It's the regular Tomahawk, and not the Tomahawk MAX? The former has older bioses that don't recognize the 3400G.
You need to download a newer bios from the product support page and make use of the board's USB Bios Flashback:

View: https://www.youtube.com/watch?v=iTkXunUAriE

Ive done this 3 times with no luck. I downloaded bios version 7C02v1E for Tomahawk B450. Don’t know if the usb has to be completely emptied with only the .ROM .