Q-Code 92: $20,000 PC build fails despite numerous component replacements, including motherboard

A 3D graphics professional was faced with the difficulties that self-assembly of a PC build. Numerous component replacements, including the motherboard, had been unsuccessful.

An assembly by Reddit user joel_motion allegedly costs $20,000. It includes AMD Ryzen Threadripper Pro 7975WX for $4000, two Zotac RTX 4090 video cards worth $2500 and 512 GB of RAM. Apparently, after a failed BIOS update, the owner was unable to successfully boot the system, which stopped at the Q-Code 92 error. Since then, despite the replacement of several suspicious components, including the motherboard, this error has not gone away.

A timeline of events can help us understand the problem, but there is still no solution. The system was first assembled in late 2024 — without a case, for initial testing, which was successful, and then the owner placed it in a Corsair 9000D Super Full-Tower case. It still worked well.

The owner then decided that a firmware update was needed Asus motherboard Pro WS WRX90E-SAGE SE to fix an incompatibility issue with one of the NVMe SSDs. For some reason, he used the «BIOS tool» (the BIOS tool) to install it, rather than the update the motherboard BIOS. Something probably happened in the process: «I had to shut down the system after the BIOS update hung up».

It was after that that the mysterious» Q-Code 92 error began to appear. Naturally, the motherboard came under suspicion — nothing else changed. The user was lucky enough to be within the RMA replacement window. However, after receiving a «used/refurbished replacement» from Asus and installing it, the same error appeared.

The owner began replacing one suspicious component after another. The replacements included «motherboard #2, processor #2, and video card #2, which still didn’t work. He then persuaded Asus to send a third motherboard #3 (this time guaranteed to be new). The system was then reassembled with a new power supply and new RAM. And once again — hello, Q-Code 92.

A Q-Code 92 error indicates a PCI bus initialization problem, which is not a very accurate indication of the cause of the problem. Tom’s Hardware notes that it is difficult to understand whether the owner has followed a reliable verification algorithm. Usually, in such cases, the system is launched with the minimum set of components required to pass POST and display the output. Then the CMOS is cleaned and the rest of the components are added one by one.

It is not clear whether the author changed absolutely ALL components, even the peripherals, including the monitor. Also, perhaps in this case, he should have tried a motherboard from another manufacturer instead of the Asus replacement. It’s worth noting that the computer’s owner appears to be a highly paid professional — perhaps he would have spent less of his precious time and nerves if he had turned to a trusted professional assembler.