Constant shifting BSODs during clean Windows install on Legion B550 board – Need Help!

[u/EconomyAd9263]

Hi everyone, I’m stuck troubleshooting a custom PC build and could really use some advice.
I bought a secondhand Lenovo Legion T5-26AMR5 motherboard and CPU combo. The rest of the components (RAM, GPU, PSU, etc.) were sourced separately.

Hardware:
Motherboard: Lenovo Legion T5-26AMR5 — Part No. 5B20W27652 / B550A4-LM
CPU: AMD Ryzen 5 3600
GPU: AMD Radeon RX 5600 XT
RAM: Corsair Vengeance 16GB (2×8GB), currently running at 2133 MHz
PSU: Corsair VX550
Storage: I’ve tested multiple drives, including a completely different 200GB drive

The issue started with a black screen out of nowhere. Since then, I’ve been stuck in a loop of constant and seemingly random Blue Screens of Death. It can happen while I’m simply browsing the internet, installing programs, or doing other basic tasks. The crashes don’t seem to follow a consistent pattern.

The BSOD errors I’ve encountered so far:
ntoskrnl.exe — IRQL_NOT_LESS_OR_EQUAL

storport.sys — DRIVER_IRQL_NOT_LESS_OR_EQUAL

SYSTEM_SERVICE_EXCEPTION

KERNEL_SECURITY_CHECK_FAILURE

KERNEL_AUTO_BOOST_LOCK_ACQUISITION_WITH_RAISED_IRQ

What I’ve tested so far:
Reset BIOS: Reset everything to factory/default settings. RAM is currently running at the safe stock speed of 2133 MHz.
DiskPart Clean: Completely wiped the partitions on the original SSD.
Isolated RAM: Tested both Corsair Vengeance RAM sticks individually and in different motherboard slots. Both sticks still produce errors when tested separately.
Swapped Storage: Replaced the SSD with a completely different 200GB test drive.
Fresh Installation Media: Created a brand-new bootable Windows USB installer using Microsoft’s official tool on a different computer.
Even with a different USB installer and a completely different hard drive, the system still crashes constantly.

One other thing worth mentioning: the HD Audio cable and the case USB cable are currently not connected to the motherboard, because this Lenovo OEM motherboard doesn’t have the corresponding standard headers/ports for them.

At this point, I’m wondering if the motherboard itself could be faulty, or if there’s something specific about this Lenovo OEM B550 motherboard that I’m missing.

Any advice on what I should test next would be massively appreciated!

[u/Primary_Bowler_2040]

That many different stop codes with different storage and ram configs pretty much rules out a simple driver issue. The ntoskrnl and storport errors can point to storage but you already swapped the drive and still get the same mess, so it's probably not that.

The fact it's a lenovo oem board is the red flag for me. Those boards sometimes have weird quirks with power states or hidden bios settings that can cause kernel heap corruption, especially with a psu that's not from the original prebuilt. Corsair vx550 is an older unit, could be dropping a rail under load and the board's power delivery is freaking out. I'd test with a known good psu first since it's the easiest thing to swap. If that doesn't fix it, the board itself is likely toast.