Issue W38/25: xAI's Grok 4 Fast and OpenAI's Agentic GPT-5-Codex - September 21, 2025
This week, xAI released its efficient Grok 4 Fast model, OpenAI shipped the agentic GPT-5-Codex for software engineering, and NVIDIA and Intel announced a major partnership to develop x86 RTX SoCs.
General News
NVIDIA is taking a $5B stake in Intel to co-develop Intel x86 RTX SoCs for PCs and data centers, featuring a design that pairs RTX and x86 chiplets via NVLink. In other news, Meta's live demo of its neural band and Ray-Ban Display experienced a brief on-stage failure, Anthropic published a detailed postmortem on three recent production issues impacting Claude's reliability, and a report claims China has banned its largest tech firms from acquiring certain NVIDIA chips.
Google DeepMind
Google DeepMind's Gemini 2.5 Deep Think achieved a gold-medal level performance at the ICPC World Finals, solving 10 out of 12 problems and publishing its solutions on GitHub. Separately, company researchers used AI to discover new families of unstable singularities in fluid dynamics equations, offering a new approach to mathematical research.
Foundation Labs & Model Updates
xAI released Grok 4 Fast, a distilled frontier model that is reportedly 40% more token-efficient and achieves speeds of 344 tokens/second in testing. OpenAI shipped GPT-5-Codex, an agentic coding assistant with task-adaptive thinking and multi-hour autonomy across its CLI, IDE, and other platforms. Mistral's Magistral 1.2 models are now multimodal, while Alibaba's Qwen3-Next-80B hybrid MoE model is now available on platforms like Together AI. In video generation, Luma Labs launched Ray3, a 'reasoning video model', DecartAI open-sourced its Lucy Edit video editing model, and Wan AI released Wan2.2-Animate-14B for character animation.
AI Developer Topics
VS Code Insiders is now integrated with the GitHub MCP server registry and is also experimenting with 200k-token contexts. The vLLM project released official aarch64 support enabling deployment on GB200 systems, while AMD pushed a major update to its ROCm stack. Hugging Face's TRL library added Context Parallelism for long-context training, and Moonshot AI open-sourced checkpoint-engine, a middleware for near-instant model weight updates.
Research News
At the ICPC World Finals, an OpenAI reasoning system solved all 12 problems under contest rules. In a collaboration, OpenAI and Apollo Evaluations observed behaviors consistent with 'scheming' in frontier models during controlled tests, urging more research into the area. In other news, Stanford researchers used generative models to design 16 viable bacteria-killing viruses from scratch, and a study showed a simple RL recipe can train single agents to rival complex multi-agent setups for research tasks.
Others Topics
A member of the /r/LocalLLaMA community shared their experience building a powerful 8x AMD MI50 rig with 256GB of VRAM for just $3,000 and another detailed their journey to purchase a modded RTX 4090 with 48GB of VRAM in Shenzhen. Additionally, an open-source mobile agent from Minitap AI claimed the #1 spot on the community-run AndroidWorld leaderboard, showcasing its ability to execute tasks in Android UIs.