AMD processors and Windows 8.1: performance but also trouble

AMD also assures that it will pay close attention to WebGL support (built into Internet Explorer 11), the standard that allows developers to create complex 2D / 3D pages and content by relying on the GPU for rendering. Windows 8.1 also supports AMD Wireless Display technology through compatibility with Miracast, the standard developed by the Wi-Fi Alliance that allows mobile devices to stream video and audio directly to TVs, without the need for cables or an existing wireless network.

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Specifically, AMD worked with Microsoft to ensure that Miracast takes advantage of the low-latency video encoding path that is part of the AMD Radeon GPUs and APUs and supports the Advanced Video Converter (better known as the Video Codec Engine or VCE).

Unfortunately, if AMD can "bully itself" for the performance improvements resulting from the combination of new drivers and Windows 8.1, the company has also a small problem with old (but really old) processors. Nothing serious or alarming, but it has emerged (and Microsoft has confirmed) that the new version of the operating system is not compatible with some old CPUs that do not have certain software instructions.

"It was a change made to improve Windows security by removing code that can't use instructions like CMPXCHG16b. According to our data, the number of processors affected is extremely small as this education has been sustained for more than 10 years, "Microsoft said.

On Wikipedia we read that the absence of CMPXCHG16b "prevents 64-bit Windows from having a user-mode address space larger than 8 terabytes" and that "the 64-bit version of Windows 8.1 requires this function". On the Neowin website, which is the source of the news, some users point to problems with old Athlon 64 X2 and also Opteron 185, for example. On the net there are also some topics on some forums where we talk about the problem, already at the time of the distribution of the Preview version this summer. No problem with Windows 8 instead.

AMD processors and Windows 8.1: performance but also trouble