Updated: Overclocker Claims To Have Found Culprit In Radeon RX 7900 XTX Temp Spikes

rx 7900 xtx vapor chamber hero
Overclocker der8auer reckons "AMD is in BIG trouble," after completing a series of tests on a batch of Radeon RX 7900 XTX graphics cards. Just before Christmas, we reported on AMD confirming it had started to investigate Radeon RX 7900 XTX and XT temperature spikes, or GPU/hotspot temperature deltas, but it looks like der8auer has beaten AMD to the punch with his "for sure" conclusion that there is a vapor chamber design flaw present in made-by-AMD (MBA) designs.

A physical flaw in the vapor chamber is quite a stretch from the previous theories regarding the observed temperature issues. A multitude of technology testers first concluded that cooler mounting pressure was behind the temperature delta problems after it was observed that reseating the cooler and repasting helped fix things. Others noted different graphics card mounting orientations made a difference.

radeon rx 7900 xtx changing orientation

In his new video, embedded below, der8auer showed his investigations initially centered on vertical vs horizontally mounting the graphics cards. He designed a jig to safely switch GPU orientation while the machine was running (see image above), so he could A/B this variable. However, once a card's GPU-hotspot deltas went up in horizontal orientation mode, there was no recovery possible, a fact which narrowed down the issue culprit to the vapor chamber.

Next, there were four potential problems with the vapor chamber to whittle down:
  • Non-optimal chamber pressure
  • Non-optimal quantity of liquid
  • Issue based on vapor chamber materials / liquid choice
  • Physical design error, so the evaporation / condensation cycle is inhibited
der8auer nods towards the fourth bullet point as the fault, after his GPU orientation switching tests. Something about the horizontal orientation means that the vapor chamber quickly gets overwhelmed under duress, and while the GPU continues to run hot under load, there is no going back. The explanation of this phenomenon is that the vapor chamber ceases to work optimally, due to the vapor simply remaining too hot to condense back to a liquid. Without the continuous liquid-gas-liquid phase change, a vapor chamber isn't operating properly.

flipping card orientation back didnt help
From vertical to horizontal and back to vertical orientation - but no recovery

Will AMD have to recall thousands of MBA design graphics cards?

Compared to the relatively small number of 12VHPWR overheating and connector melting problems reported, der8auer says that "thousands" are affected by this AMD Radeon overheating issue. An RMA might be necessary "for the entire MBA cooler series" equipped graphics cards, added the TechTuber. Remember, many if not all of AMD's graphics cards partners (AIBs) have marketed MBA designs with their own packaging and logo. In summary, both AMD and NVIDIA have released next-gen designs with big potential problems in 2022, and people who live in glass houses shouldn't throw stones. Hopefully NVIDIA execs will resist the temptation to tease AMD, and ultimately customers who bought these next-gen products, as both firms make their fair share of blunders.

What do you think of der8auer's conclusions here? Let us know in the comments.

Update from AMD (1/4/2023 12:45pm ET)

AMD has since provided an official response for this issue and is addressing it with any affected customers:

We are working to determine the root cause of the unexpected throttling experienced by some while using the AMD Radeon RX 7900 XTX graphics cards made by AMD. Based on our observations to-date, we believe the issue relates to the thermal solution used in the AMD reference design and appears to be present in a limited number of the cards sold. We are committed to solving this issue for impacted cards. Customers experiencing this unexpected throttling should contact AMD Support.