ASUS has announced that it will be working on a replacement plan for their Maximus Z690 Hero motherboards. The Z690 is an Intel’s latest chipset for 12th generation Alder Lake processors. This issue affects motherboards with the part number: 90MB18E0-MVAAY0 and serial numbers starting with MA, MB, or MC.

The Maximus Z690 is ASUS’ high end motherboard.
On December 19th, Redditor u/TheMaxXHD posted ASUS ROG Z690 Hero Motherboard; Two mobos dead in 3 days, one caught on fire where he describes his experience where a component on the motherboard caught fire.

That component was a MOSFET, a transistor used to deliver 5V of power to various components including DDR5 RAM memory. MOSFETs are the most sold device in world history and are practically in every modern-day computer equipment.
Redditor u/Duhjahno posted a similar experience of his ASUS ROG Maximus Z690 Hero melting and shared pictures showing his motherboard’s MOSFETs melted down.
YouTuber BuildZoid reviewed this in his video My thoughts on the ASUS Maximus Z690 Hero failures – YouTube

BuildZoid went on to discover the root cause of the problem. The MOSFETs were installed backwards.
Since then, ASUS made an announcement on Tuesday, December 28th stating that they would be working with local government agencies on a replacement plan.
Asus, a Taiwan company, is the world’s 5th-largest PC vendor (January, 2021). The ASUS ROG (Republic of Gamers) brand has won several awards over the years and the ASUS ROG Maximus Hero has itself earned 28 awards from various blogs and several raving reviews:
If you have this motherboard, you should return it as soon as possible. If you are planning to buy a 12th generation Intel Chipset from any prebuilt gaming PC’s or build parts lists, make sure they do not have the ASUS Maximus Z690 Hero motherboard with part number 90MB18E0-MVAAY0 and serial numbers starting with MA, MB, or MC.