[SOLVED] New Setup - System Worked Once but now cannot get into BIOS. Please Help!

[booournz]

Hello fine citizens of tom's Hardware!

After rereading my mobo manual several times, 50+ articles/threads later, I've finally come to you all...defeated...in hopes for any ray of light.

System:
CPU: AMD Ryzen 5 3600 6-Core, 12-Thread Unlocked Desktop Processor
RAM: Corsair Vengeance LPX 16GB (2x8GB) DDR4 DRAM 3200MHz C16
Mobo: ASUS B450-I ROG Strix Gaming AMD AM4 mITX Motherboard
GPU: MSI VGA Graphic Cards RX 580 ARMOR 8G OC
SSD: Samsung 500GB 970 EVO Nvme M2 Solid State Drive
SSHD: Seagate FireCuda 2 TB 2.5" 5400RPM Hybrid Internal Hard Drive
PSU: NZXT H1
AIO: NZXT H1

I've watched 6 how-to-build videos on YouTube before receiving my parts to finally build this guy myself (actually mirrored a couple components from OptimumTech's build here).

Symptoms:

• Cannot load into BIOS (black screen no output - monitor hooked into my GPU via HDMI)
• Mobo's LED lights: Red > White alternating (CPU > VGA , respectively) flashes for ~1 second each. This will continue until white VGA LED remains on (happens about one in every three resets)
• When the Red/White mobo LED's flash in the above pattern, the NZXT H1's AIO CPU fan and my GPU's fans will also "pulse" to the flashes.
• Mobo's RGB side lighting works as expected (always on)
• Throughout this, the NZXT H1 PSU fan does not spin (only spins briefly when I power down the system)

Troubleshooting:

• As far as connections, I triple checked to make sure they (8pin, 24pin, usb, sata, cpu fan, aio pump, audio, front panel) are all secured - essentially followed step by step all the video tutorials on the NZXT H1 setup
• CPU pins are not bent, fits snugly on Mobo
• RAM setup: tried different startup variations (x6 permutations: 2 sticks, stickA only in slot 1, stickB only in slot 1, etc)
• CMOS: pulled out battery with various wait times (5 min, 15 min, 24 hrs, 48 hrs) - still no dice even holding case's power button to discharge capacitors
• CMOS jumper pins: used screwdriver to short the 2 pins specified in p.22 of manual
• GPU: tested to working in my other build
• I've also closely reviewed and performed the checklist from this thread

Additional Background:
Upon my initial setup, I did get this setup to boot and install Windows. However, the system wasn't able to recognize the Seagate Firecuda SSHD secondary (Samsung SSD is primary boot). Apparently this Seagate issue is a known issue for Windows10, so I regrettably used the driver verifier to address this. Perhaps the Window's driver verifier crashed my system, but now I cannot even do a CMOS reset and get to the BIOS screen.

Any assistance would be greatly appreciated, thanks in advance!



Update:
5/13/20: got a replacement motherboard (the same ASUS B450-I) and rebuilt - same blinking issue. Requested exchange of the PSU as I suspect that is the culprit. Fingers crossed.

 

[rgd1101]

motherboard box have the sticker that said support 3000 series?

 

[booournz]

I believe so - are you referring to:

"AMD RYZEN 3000 DESKTOP READY"
"AMD RYZEN 2000 DESKTOP READY"

The mobo box has both of these ^

 

[booournz]

Update: Got it working
6/7/20:

• Rookie mistake with the Firecuda: I did not format the disk which is why it was not partitioned.
• Replaced motherboard and new case with new power supply (all exact same models)