MSI admits faulty heatsink design for cracked Z790 chipsets, begins replacing faulty units

MSI Z790 Tomahawk WiFi
(Image credit: MSI)

We reported yesterday that users have been complaining for months about MSI Z790 motherboard issues that resulted in systems not powering on at all or failing repeatedly during POST (Power On Self-Test). Today, MSI issued a statement via Reddit confirming the findings of YouTuber Joshi Repair, who suggested that cracks found on the PCH (Platform Controller Hub) of an MSI Z790 Tomahawk WiFi motherboard resulted from a factory fault.

"We have discovered a minority of units might encounter non-functional PCH potentially resulting in Dead on Arrival (DOA) of the motherboard products. We have isolated the cause to a previous used chipset heatsink screw design and have taken proactive measures to address this issue," MSI explained in a statement. "A revised chipset heatsink screw design has been implemented into our production, and the known cases have been resolved." 

MSI continued, "We uphold high standards of responsibility and accountability, and want to assure affected customers can promptly receive product replacements." Customers are urged to contact the closest regional MSI service center to initiate an RMA replacement for a Z790 motherboard afflicted with a defective PCH.

While it's commendable that MSI is replacing the boards after the failures received wider coverage by the media, there are reports of cracked PCHs with the Z790 Tomahawk WiFi via Reddit that go back at least nine months. In one case, Redditor encephalophiliac received a brand new Z790 Tomahawk WiFi motherboard from Newegg that failed to power on. The user found a crack after removing the PCH heatsink and decided to RMA the motherboard to Newegg. To add insult to injury, encephalophiliac received an RMA replacement from Newegg, which was also DOA.

MSI did not confirm how many of its Z790 motherboards shipped with the faulty heatsink screw. In addition, the company only confirmed issues with the Z790 Tomahawk WiFi and did not mention other Z790 SKUs that could be affected. However, it's alleged that the number of affected motherboards could be in the hundreds.

The good news here is that the root cause of the DOA motherboards has been identified, and a fix is currently being implemented on MSI's production lines. For customers in the United States, you can start the RMA process for a defective motherboard via the MSI Service and Support website.

Brandon Hill

Brandon Hill is a senior editor at Tom's Hardware. He has written about PC and Mac tech since the late 1990s with bylines at AnandTech, DailyTech, and Hot Hardware. When he is not consuming copious amounts of tech news, he can be found enjoying the NC mountains or the beach with his wife and two sons.