Microsoft vet Raymond Chen first told the story of HLT and Windows 95 more than 20 years ago. The instruction tells the CPU to effectively shut itself down until the next hardware interrupt – ideal for laptops, since power consumption would be hugely reduced.

Microsoft had it implemented and working in Windows 95, but found that there were some devices out there, including from a "major manufacturer," that would be locked up unrecoverably by the instruction. Not wanting to be blamed, Microsoft pulled it.

So why didn't Microsoft just special-case devices that would be bricked by the HLT instruction in Windows 95? Chen has finally explained.

The answer is simple – Microsoft wasn't sure how many susceptible devices were already out in the wild, and so opted to leave it out rather than take

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