How Much Context Fits Beside a 12B on an 8 GB GPU? Gemma 4 12B's Context Cache on an RTX 3050

Recent guides detail deploying Google's Gemma 4 models on an 8 GB NVIDIA RTX 3050 using llama.cpp. For Gemma 4 12B, the focus is on context cache and drafter settings for long agentic coding sessions. For the Gemma 4 26B A4B MoE, which exceeds GPU memory, llama.cpp manages experts in system RAM via CPU. Both implementations utilize Python MCP tools to measure generation speed, context capacity, and answer consistency across different model sizes.