Why Qwen3.5-122B-A10B pressures system RAM
Qwen3.5-122B-A10B is Mixture-of-Experts: inference activates 10B active/token, but VRAM/RAM must usually hold the full ~122B expert set for fast routing. At Q4 the weight slab is ~68.6GB before KV (~0.02GB at 8K) and ~8GB OS/runtime overhead — totaling ~76.6GB raw, rounded to a 96GB kit. Stretching toward the full 262K-token window multiplies KV far faster than weights; that is the usual “I bought enough RAM for the model but still OOM” failure on Alibaba Qwen MoE pages.
What RAM kit to buy
Buy a matched dual-channel DDR5 kit at 96GB for Qwen3.5-122B-A10B (EXPO/XMP only if stable). Avoid single-stick installs — local inference is bandwidth-sensitive when layers spill to host memory. Pair with 4x RTX 3090 / 4090 (96GB VRAM) or Apple Mac Studio (128GB Unified Memory) when staying in the Multi-GPU Workstation / Mac Studio tier, and keep 20–30% RAM free for the OS + browser.
Workload notes
Qwen-family models like Qwen3.5-122B-A10B often ship strong coding/agent variants; leave RAM for tool runners and browser IDEs beside the weights. At 122B, Qwen3.5-122B-A10B sits in the large local-LLM band: Q4 on a strong GPU is realistic, FP16 usually is not on consumer cards. Release window noted as 2025/2026; always re-check the model card before buying hardware for a specific checkpoint.





