Can Desktop PC · GeForce RTX 4090 · 64 GB RAM run GLM-5.3-Flash (320B-A18B)?
24 GB VRAM + 64 GB RAM · 1008 GB/s memory bandwidth · GLM-5.3-Flash (320B-A18B) has 320B parameters (18B active per token).
Short answer
No. It doesn't fit in memory.
Needs ≈148 GB but only ≈75 GB of VRAM + system RAM is available after the OS and other apps.
Why it doesn’t fit
Even its smallest practical version (Q3_K_M) needs about 148 GB for the model, its context memory and the runtime. After Windows (≈7.7 GB), a browser with a few tabs (≈3.0 GB) and Open WebUI (≈1.0 GB), Desktop PC · GeForce RTX 4090 · 64 GB RAM has about 75 GB left, so it’s 73 GB short.
Ways to make it work
Close everything else
Not enough on its own: with every other app closed it’s still about 70 GB short.
Pick a smaller model from the same family
Get more memory
You’d want at least 160 GB of VRAM plus RAM in total. The machines below are the cheapest that run it comfortably.
Check your exact setup
These pages assume typical settings. A shorter context or a lighter chat app can change the answer.
Check Desktop PC · GeForce RTX 4090 · 64 GB RAM
The same applies to every workload we rate (chat, coding questions, coding in a repository, agentic coding and long documents): they all need at least as much memory as chat.
Other models for Desktop PC · GeForce RTX 4090 · 64 GB RAM
The best-rated models for chat on this machine.
- Qwen3.6 35B-A3B240–330 tok/sExcellent
- Gemma 4 26B-A4B160–220 tok/sExcellent
- LFM2.5 24B-A2B360–490 tok/sExcellent
- Qwen3.5 35B-A3B240–330 tok/sExcellent
- GLM-4.7-Flash (30B-A3B)240–330 tok/sExcellent
- gpt-oss-20b≈210 tok/sExcellent
Cheapest machines for GLM-5.3-Flash (320B-A18B)
Hardware rated comfortable or better for chat, lowest price first.
- Mac Studio M5 Ultra 256 GB$6,299 · 35–60 tok/sExcellent
- Mac Studio M3 Ultra 256 GB$6,299 · 25–35 tok/sExcellent
- Mac Studio M5 Ultra 512 GB$7,099 · 30–45 tok/sExcellent
- Mac Studio M3 Ultra 512 GB$7,099 · 25–35 tok/sExcellent
Same chip, other memory: 32 GB
Different tool, context size or workload?
These pages use typical settings. The full check models your exact setup.