NVIDIA's next-gen B300, GB300 have 'severe thermal issues' but there's plenty of time to fix it

NVIDIA's next-gen B300 and GB300 AI GPUs are currently being tested, with some news that AOS's DrMOS were experiencing "severe thermal issues".

In a new post on X and a more detailed post on Medium, insider Ming-Chi Kuo says that the DrMOS chips are currently being tested for NVIDIA's new GB300/B300 system, and that they're AOS's 5x5 and MPS's 5x6, with Kuo's supply chain survey indicating that AOS's DrMOS were experiencing severe thermal issues.

Kuo said: "With GB300/B300 still some time away from mass production, This event doesn't mean that AOS can't eventually benefit from GB300/B300. However, to avoid repeating delays seen with GB200/B200, NVIDIA's efforts to seek alternative 5x5 DrMOS suppliers or to accelerate testing of MPS's 5x6 DrMOS could impact the market's high expectations for AOS's orders in the near term".

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In full, Kuo provided the following analysis:

1. NVIDIA prioritized testing AOS's 5x5 DrMOS for two reasons: 1) To strengthen its bargaining power against MPS to lower costs, and 2) AOS has more excellent expertise in the design and production of 5x5 DrMOS.
2. The DrMOS itself may not solely cause the thermal issue but could also result from insufficient optimization in other designs, such as system thermal management.
3. If the issue remains unresolved, NVIDIA may take proactive measures to avoid delays in GB300/B300 mass production. These could include 1) Engaging alternative 5x5 DrMOS suppliers, such as requesting test samples from MPS, and 2) Accelerating testing of MPS's 5x6 DrMOS. Such actions could dampen the market's highly optimistic outlook on AOS's future orders in the short term.
4. 5x6 DrMOS comes with higher costs but offers better thermal performance. If the thermal issue with 5x5 DrMOS persists, the likelihood of NVIDIA switching to 5x6 DrMOS will increase, potentially benefiting MPS, which has a technology advantage in the 5x6 design.