HomeCan I run it?GLM-4.5-AirGLM-4.5-Air on an RTX 4090
No. GLM-4.5-Air at Q4_K_M needs about 78.0 GB, and the GeForce RTX 4090 has 24.0 GB usable at a ~4k context.
Can I run GLM-4.5-Air on an RTX 4090?
GLM-4.5-Air at Q4_K_M needs about 78.0 GB, and the GeForce RTX 4090 has 24.0 GB usable. That figure is 24 GB of VRAM on the spec sheet, of which 24.0 GB is usable for weights and cache, at 1008 GB/s memory bandwidth. Zhipu’s GLM-4.5-Air, a large model in the roughly 80 GB Q4 class — above a 24 GB card, below full DeepSeek-R1. These are estimates from our formula, not measured benchmarks.
- Quant that fits
- None of Q4, Q8 or FP16 needs 78.0 GB
- Memory needed
- 78.0 GB at Q4_K_M, ~4k context
- Usable VRAM
- 24.0 GB of 24 GB VRAM
- Est. tokens/sec
- n/a does not fit
Memory at each quant
| Quant | Need vs 24.0 GB | Verdict |
|---|---|---|
| Q4_K_M | 78.0 GB | Q4Won’t fit |
| Q8_0 | 136.0 GB | Q8Won’t fit |
| FP16 | 255.1 GB | FP16Won’t fit |
Estimated tokens per second
No speed estimate: GLM-4.5-Air does not fit in the 24.0 GB this machine can use, so we do not publish a tokens/sec figure for CPU offload.
Context headroom
Even at a short ~4k context, the weights do not fit. Extending context would only increase the gap.
| Context | KV cache (FP16) | Total at Q4_K_M | Verdict |
|---|---|---|---|
| 4k | 0.8 GB | 78.0 GB | Won’t fit |
| 8k | 1.5 GB | 78.8 GB | Won’t fit |
| 16k | 3.1 GB | 80.3 GB | Won’t fit |
| 32k | 6.2 GB | 83.4 GB | Won’t fit |
| 64k | 12.3 GB | 89.6 GB | Won’t fit |
| 128k | 24.7 GB | 101.9 GB | Won’t fit |
What to do instead
- Run R1 Distill 32B instead (23.8 GB at Q4). It is a different model, not a drop-in, but it does fit this machine.
- To hold GLM-4.5-Air at Q4, you need about 78.0 GB. The MacBook Pro M5 Max 128GB has 96.0 GB usable ($6699 Apple list price, 14-inch M5 Max 18C CPU/40C GPU, 128GB/2TB).
- CPU offload can load the weights anyway, but it is slow. We do not publish an offload tokens/sec figure.
- Full hardware list: GLM-4.5-Air. Specs for this machine: GeForce RTX 4090.
Other hardware for GLM-4.5-Air
- GLM-4.5-Air on an RTX 5090Won’t fit
- GLM-4.5-Air on dual RTX 3090sWon’t fit
- GLM-4.5-Air on a Mac mini 64GBWon’t fit
- GLM-4.5-Air on a Mac Studio 256GBFits
- GLM-4.5-Air on an RTX 3090Won’t fit
Other models on an RTX 4090
- Qwen3-32B on an RTX 4090Tight
- Qwen3-30B-A3B on an RTX 4090Tight
- Qwen3.8-27B on an RTX 4090Fits
- Gemma 3 27B on an RTX 4090Fits
- Gemma 4 31B on an RTX 4090Tight
- gpt-oss-20b on an RTX 4090Fits
Quick answers
- Can I run GLM-4.5-Air on an RTX 4090?
- No. GLM-4.5-Air at Q4_K_M needs about 78.0 GB, and the GeForce RTX 4090 has 24.0 GB usable.
- How much VRAM does GLM-4.5-Air need?
- About 78.0 GB at Q4_K_M, 136.0 GB at Q8_0 and 255.1 GB at FP16, estimated for a ~4k context.
- How fast is GLM-4.5-Air on an RTX 4090?
- We do not estimate tokens/sec when the model does not fit. CPU offload is possible but slow.
- What context length can I use?
- The weights already do not fit, so longer context is not the limiting factor.