AMD updates
AMD has published an update on its processor security in the wake of the Spectre and Meltdown saga. In summary it echoes Intel in that "security is our top priority and we are continually working to ensure the safety of our users as new risks arise". Discussing more timely matters, AMD says it has been working closely with OS providers to patch GPZ Variant 1 (Spectre) and OS and motherboard makers to patch GPZ Variant 2 (Spectre). For GPZ Variant 3 (Meltdown), AMD still asserts that "no mitigation is required," as its processors are not susceptible.
For GPZ Variant 1, AMD mentions that it has been working closely with Microsoft to patch for AMD processors old and new. Unfortunately there have been reports on some AMD Windows PCs 'bricking', especially with patches for older AMD processors (AMD Opteron, Athlon and AMD Turion X2 Ultra families). However, safe working updates from Microsoft should resume by next week.
For GPZ Variant 2, AMD says that while its architectures make it "difficult to exploit," it is still working with OS software developers and on issuing a microcode update. Ryzen and EPYC processor microcode updates will be available this week - from both system and OS vensors.
Moving on to GPUs, AMD says that the Radeon architectures don't use speculative execution "and thus are not susceptible to these threats".
Nvidia updates
Neatly linking to where we left off with AMD, Nvidia has issued a security bulletin regarding its driver updates for CPU speculative side channel vulnerabilities. Like AMD it asserts that its GPUs are "immune" for architectural reasons. However it is supplying driver updates to "mitigate the CPU security issue".
Nvidia's software developers will be, like AMD, providing collaborative help to OS vendors to strengthen mitigations for affected CPUs that could be affected by For GPZ Variant 1 and 2 (Spectre).