Question 5900x Wont post in 3 Different Mbs?

[Gabefromnj]

I just bought a 5900x today. I first tried it on a asus tuf gaming x570-plus and it would not post. I could not get the MB to flash, so I tried a gigabyte x570 aorus elite. Same issue. Finally, I got a msi x570 gamers edge to flash to the latest bios. I turned it on, thinking I was going to be in wonderland with my new 5900. All I got was a led error for the cpu.
I have a corsair 750 watt psu, with the main mb power and 8 pin connected. Also a 3070 fe. I took out all but one ram stick. I flow this forum a lot and this is my first time posting. I would really appreciate any insight.

 

[Third-Eye]

I just bought a 5900x today. I first tried it on a asus tuf gaming x570-plus and it would not post. I could not get the MB to flash, so I tried a gigabyte x570 aorus elite. Same issue. Finally, I got a msi x570 gamers edge to flash to the latest bios. I turned it on, thinking I was going to be in wonderland with my new 5900. All I got was a led error for the cpu.
I have a corsair 750 watt psu, with the main mb power and 8 pin connected. Also a 3070 fe. I took out all but one ram stick. I flow this forum a lot and this is my first time posting. I would really appreciate any insight.

How exactly did you try flashing the bios on each motherboard?

The Asus board requires a non G series Ryzen 2000/ 3000 CPU to flash the bios and the Gigabyte and MSI boards can be flashed from a specific rear I/O USB port without an older model CPU that the Asus board requires. I know for sure the MSI board can be bios flashed without a CPU installed.

 

[Jacozeelie]

Sounds like a faulty cpu. Turn over the cpu and check if it has bend pins.

 

[Gabefromnj]

How exactly did you try flashing the bios on each motherboard?

The Asus board requires a non G series Ryzen 2000/ 3000 CPU to flash the bios and the Gigabyte and MSI boards can be flashed from a specific rear I/O USB port without an older model CPU that the Asus board requires. I know for sure the MSI board can be bios flashed without a CPU installed.

I flashed the msi board by using the flash button and a USB stick. It's flashed to thr latest version of bios. I'm wondering if there is any one that I should try. I did not have any success flashing the gigabyte board. I pressed the flash button with the USB stick installed and it did nothing. For sake of sanity at this point, I'll deal with the msi just to get it running

 

[Th4nato5]

I flashed the msi board by using the flash button and a USB stick. It's flashed to thr latest version of bios. I'm wondering if there is any one that I should try. I did not have any success flashing the gigabyte board. I pressed the flash button with the USB stick installed and it did nothing. For sake of sanity at this point, I'll deal with the msi just to get it running

Which file format does your USB stick have? IIRC, I am pretty sure you are supposed to have a FAT32 stick (don't quote me on this, but check on the internet because I remember people having problems with flashing due to the file formatting on the stick).