Internlm Chat 20B — Hardware Requirements & GPU Compatibility
Chat
Internlm Chat 20B is a 20B-parameter open language model from InternLM in the InternLM family. It supports a context window of up to 4,096 tokens. At FP16 it needs about 42.82 GB of VRAM — see which GPUs and Macs can run it below.
992 downloads
134 likesSpecifications
- Publisher
- InternLM
- Family
- InternLM
- Parameters
- 20B
- Architecture
- InternLMForCausalLM
- Context Length
- 4,096 tokens
- Vocabulary Size
- 103,168
- License
- Apache 2.0
Get Started
HuggingFace
How Much VRAM Does Internlm Chat 20B Need?
Select a quantization to see compatible GPUs below.
| Quantization | Bits | VRAM | + Context | File Size | Quality |
|---|---|---|---|---|---|
| FP16 | 16.00 | 42.8 GB | 45.3 GB | 40.00 GB | Full half-precision — baseline for inference |
Which GPUs Can Run Internlm Chat 20B?
FP16 · 42.8 GBInternlm Chat 20B (FP16) requires 42.8 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 56+ GB is recommended. Using the full 4K context window can add up to 2.5 GB, bringing total usage to 45.3 GB. No single GPU has enough memory — multi-GPU or cluster setups are needed.
Which Devices Can Run Internlm Chat 20B?
FP16 · 42.8 GB11 devices with unified memory can run Internlm Chat 20B, including NVIDIA DGX H100, NVIDIA DGX A100 640GB, Mac Studio M4 Max (64 GB).
Runs great
— Plenty of headroom
Benchmarks
View all 3 →Related Models
Frequently Asked Questions
- How much VRAM does Internlm Chat 20B need?
Internlm Chat 20B requires 42.8 GB of VRAM at FP16. Full 4K context adds up to 2.5 GB (45.3 GB total).
VRAM = Weights + KV Cache + Overhead
Weights = 20B × 16 bits ÷ 8 = 40 GB
KV Cache + Overhead ≈ 2.8 GB (at 2K context + ~0.3 GB framework)
KV Cache + Overhead ≈ 5.3 GB (at full 4K context)
VRAM usage by quantization
FP1642.8 GBFP16 + full context45.3 GB- Can NVIDIA GeForce RTX 5090 run Internlm Chat 20B?
No — Internlm Chat 20B requires at least 42.8 GB at FP16, which exceeds the NVIDIA GeForce RTX 5090's 32 GB of VRAM.
- Can I run Internlm Chat 20B on a Mac?
Internlm Chat 20B requires at least 42.8 GB at FP16, which exceeds the unified memory of most consumer Macs. You would need a Mac Studio or Mac Pro with a high-memory configuration.
- Can I run Internlm Chat 20B locally?
Yes — Internlm Chat 20B can run locally on consumer hardware. At FP16 quantization it needs 42.8 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.
- How fast is Internlm Chat 20B?
At FP16, Internlm Chat 20B can reach ~68 tok/s on AMD Instinct MI300X. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.
tok/s = (bandwidth GB/s ÷ model GB) × efficiency
Example: AMD Instinct MI300X → 5300 ÷ 42.8 × 0.55 = ~68 tok/s
Estimated speed at FP16 (42.8 GB)
~68 tok/s~51 tok/s~42 tok/sReal-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.
- What's the download size of Internlm Chat 20B?
At FP16, the download is about 40.00 GB.
- Which GPUs can run Internlm Chat 20B?
No single consumer GPU has enough VRAM to run Internlm Chat 20B at FP16 (42.8 GB). Multi-GPU or professional hardware is required.
- Which devices can run Internlm Chat 20B?
11 devices with unified memory can run Internlm Chat 20B at FP16 (42.8 GB), including Mac Mini M4 Pro (48 GB), Mac Pro M2 Ultra (192 GB), Mac Studio M2 Ultra (192 GB), Mac Studio M4 Max (128 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.