Grok 3 vs Phi-3.5-MoE Instruct

Grok 3

xAI

Grok 3, released by xAI in February 2025, is a large language model trained on xAI's Colossus supercluster with substantially increased compute over previous generations. It features a 1M token context window, RL-enhanced Think mode for extended reasoning, and demonstrated strong results on mathematics, coding, and scientific benchmarks. Grok 3 targets complex reasoning, real-time information tasks via X platform integration, and agentic workflows via the xAI API.

Phi-3.5-MoE Instruct

Microsoft

Phi-3.5-MoE-instruct is a sparse mixture-of-experts model from Microsoft's Phi research team, released in August 2024 with 42 billion total parameters across 16 experts and approximately 6.6 billion active parameters per forward pass. The model applies Microsoft's small-data, high-quality training philosophy — developed across earlier Phi generations — to a MoE architecture, targeting reasoning quality comparable to much larger dense models at a fraction of the inference compute. Released under the MIT license, it was notable in the research community for demonstrating that MoE efficiency gains could be realized at smaller total parameter counts than typical large-scale MoE deployments.