1 HN user recommended this demo1 month2021–2022score 1
Years with an HN recommendation, 2007–2026
Cited in threads on chip packaging and cooling as a vivid look at vintage IBM mainframe module construction.
Dave Jones of EEVblog tears down a 1991 IBM 9121 thermal conduction module from a System/390 mainframe, a 63-layer ceramic hybrid module with 2772 pins worth about $250,000, and demonstrates a BGA desoldering technique.
“Dave from EEVBlog also made a video about it” (HN, 2021)
All the vintage mainframe stuff is pretty mind blowing. There is an awesome hidden gem on YouTube: CPU Galaxy. He has a huge collection of vintage CPUs. IBM 9121 Mainframe CPU [link] Dave from EEVBlog also made a video about it [this video]
EEVblog teardown of a vintage IBM mainframe processor module.
The thermal solution and packaging looks a lot like mainframe systems from the 80s (IBM, Siemens, Japanese). Siemens H100: [link] [link] IBM: [this video]
Shows 1980s IBM mainframe thermal and packaging similar to Dojo.
This one does[1]. It have a bunch of pistons on springs touching each chiplet, all in mineral oil. Price bit out of range for typical desktop user tho * [this video]
Shows IBM module with spring-loaded pistons cooling each chiplet.
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