MSI Z790 motherboards reportedly failing with cracked PCH chipset — a manufacturing error may have affected a few hundred units (Updated)

UPDATE 4/3/2024 3:20pm PT: MSI has reached out with a statement on the matter and is now replacing faulty units. You can read more about that here. 

Original article:

Users have reported that their MSI Z790 motherboards are failing and refusing to boot. Upon further investigation, the PCH (Platform Controller Hub) chipset has cracks that have made the motherboards unusable. Reports have come in through Reddit and other discussion posts, and repair technicians have noticed and diagnosed the issue, claiming that this issue is more widespread that at first believed.

Intel Z790 motherboards have been available since Q4 2022 for 12th, 13th and 14th Gen Core CPUs. Reports of MSI motherboard failures only started surfacing on subreddits and discussion boards a few months ago. What was first thought to be a limited occurrence may be a more widespread issue, as some users reported a similar failed BOOT process over a year ago. MSI replaced the affected motherboards at the time.

YouTuber and repair technician Joshi Repair recently diagnosed an MSI Z790 Tomahawk WiFi whose PCH heatsink was not removed before the video, showcasing this common issue. The repair tech suggests that the crack was caused by a factory fault. The result is that these motherboards will either not power on or will repeatedly cycle during POST (Power On Self-Test).

Removing the PCH heatsink and cleaning the thermal paste shows what appear to be surface-level scratches. However, with the help of a thermal camera and isopropyl alcohol, powering up the motherboard shows that the scratches are in fact cracks in the chip. The only fix at this point was to return the motherboard to the manufacturer, or purchase a replacement board.

With a single sample, it would be difficult to accurately attribute these cracks to a single root cause, though speculation has occurred among enthusiasts and repair techs. One possibility is that the damage happened during the soldering process and isn't just a bad batch. Another suggestion is that the cracks may have been formed when the chipset heatsinks were installed, based on the direction of the cracks and the mounting holes.

Regardless of the cause, the cracked Z790 PCH chips have so far only been found on MSI motherboards. That points to the problem being specifically with MSI and its factory. These motherboards were sent to Poland, and there are a couple of hundred similar cases.

Manufacturing defects can happen, irrespective of the brand. However, we need to ask how such motherboards were able to pass through Quality Control, assuming they failed to complete the POST process. More critically is what happens next and how effectively these issues are addressed.

At the time of writing, MSI has not issued any official notice regarding the matter, nor are there any plans to make a batch recall. If there is a problem with a specific batch, or with its Z790 boards in general, it would be best for MSI to provide an easy replacement for affected motherboards — both for already reported failures as well as potential future failures. Enabling a hassle-free replacement and repair on behalf of its customers ultimately is the only proper course of action.