Microsoft's claim was "Microsoft has determined that some AMD chipsets do not conform to the documentation previously provided to Microsoft to develop the Windo

Microsoft's claim was "Microsoft has determined that some AMD chipsets do not conform to the documentation previously provided to Microsoft to develop the Windows operating system mitigations to protect against the chipset vulnerabilities known as Spectre and Meltdown"[1], and their docs simply suggest asking AMD for more details[2]. So it sounds like it was probably specific chipsets and not CPUs, but who knows. [1] - https://www.engadget.com/2018/01/09/microsoft-halts-meltdown-spectre-amd-patches/ https://www.engadget.com/2018/01/09/microsoft-halts-meltdown... [2] - https://support.microsoft.com/en-us/help/4056892/windows-10-update-kb4056892 https://support.microsoft.com/en-us/help/4056892/windows-10-...