Question Ryzen 9 5900X with ROG Strix X570-E Gaming - new PC build does not start - red LED keeps blinking

[amdryzenguy]

Just put together a new system.

AMD Ryzen 9 5900X
ASUS ROG Strix X570-E Gaming
Corsair CX 750M PSU (750 W)
Sabrent 1 TB NVMe SSD
2 X 16GB Corsair DDR4 RAM
Corsair 4000D Airflow case

However, nothing turns on when I press the power button.
All that happens is the red LED light next to the 4-pin and 8-pin ATX power connector turns on and keeps blinking roughly every 1 second. (This is not the QLED.)
I have the 24-pin connector and the 8-pin connector plugged since the Corsair PSU only has those two cables. Nothing is plugged in to the 4-pin slot on the motherboard.

These are things I've tried so far:

• Read the sticky post here on the POST problems on this forum
• Removed CMOS battery and with and without some of the components. Multiple variations.
• Tried with 0, 1, and 2 RAM sticks installed.
• Did the Corsair website PSU paper clip test. It works. PSU fan turns on.

I tried to do the USB BIOS Flashback. Don't have a Windows machine. So, I just manually renamed the downloaded .CAP file to SX570E.CAP from the Linux command line. Is this a problem?
Formatted a USB flash drive to FAT and plugged it in. But when I press the BIOS Flashback button, absolutely nothing happens. I'm doing this with the CPU installed. Online reports said I could do it this way.

Questions:

• For BIOS Flashback method, do I need to remove the CPU from the motherboard before trying to flash? Do I need to remove all components?
• Is there a way to find out what the current BIOS version is? PC does not turn on. Wondering if there is some number on the motherboard that can point me to this info?

What else can I try to get the PC to start? Frustrating so far. :-(

 

[punkncat]

What GPU are you using?

5900X has no iGPU so without one you won't see anything regardless.

 

[amdryzenguy]

Darn. You are right. I didn't know you had to have a GPU for the 5900X. (Been 5 years since I built a PC and assumed all CPUs come with graphics.)

I pulled out an XFX R7750 GPU from my other currently working PC and put it in.

XFX HD 7750 2 GB Specs

AMD Cape Verde, 800 MHz, 512 Cores, 32 TMUs, 16 ROPs, 2048 MB GDDR5, 1125 MHz, 128 bit

www.techpowerup.com

But, no luck. Same thing happens. Nothing turns on but for the red LED that keeps blinking once a second or so. What does that LED indicate?

Any other ideas?

 

[punkncat]

I may not be understanding your issue with the PSU connections properly.

The PSU you have is semi modular, meaning there are some plugs that are 'permanent' and then there should be additional plugs for the peripherals.
The 24 pin only goes where it can go. There are going to be a set of likely 2x4pin marked CPU and then more than likely one of the modular cables should be marked PCI. You MUST use the correct plug in the correct place.

Looking at pics seems to indicate there are 12 pins (1x4, 1x8) for the CPU power (on the mobo) and you only have (8) from the PSU?
It might be that you need to return the PSU and get one that has the appropriate connectors.
I have seen reviews that indicate that in some cases you can leave (some of) that unplugged, but am not familiar enough with this mobo to know if that applies. Certainly, in the instance that you are utilizing a Ryzen 9 it is likely to need all of them.

 

[amdryzenguy]

I think you got it. In addition to the main 24 pin connector, there are 1x4 and 1x8 slots on the MB but I only have 1x8 from the PSU. I read conflicting reports about if that 1x4 is needed or not. But, as you say, given that it's a Ryzen 9, looks like I'm going to need a different PSU with all connectors. I'll update this post after I get one. Hopefully, that fixes the issue.

Thanks for the help. I appreciate it.

 

[amdryzenguy]

I tried one other thing based on a review by someone on this motherboard's Amazon product page. I disconnected the front panel USB-3 connector cable from the motherboard. I pressed the power button and just like that it came on - PSU fan started spinning, STRIX logo LED turned on. Now I need to put back that old GPU and go from there.
This is so bizarre - a USB-3 cable of all things.

 

[docbooth]

I finished my Ryzen 9 5900X, 128GB, STRIX 570E build the day of your last posting. There is a posting in this forum explaining the need for PSU power to the sockets between the CPU and I/O on the edge of the MOBO. I would find the post and link it but I am celebrating getting COVID version 1 two years ago by getting version ?3? Mine booted just fine in spite of my cheap English case and is waiting for the Linux install for a dual boot option. Good Luck!