Skip to content
GPU Ninja
≈ 6.4 GB

Workload planner

Llama 3.1 8B Instruct (Q4_K_M) at Q4_K_M · 8K context · 1 sequence at 30 tok/s

Needs about 6.4 GB of memory, 1.23 FP16 TFLOPS and 255 GB/s.

Workload estimate

  • Catalogue loading
  • Card sizes loading

Estimate

Memory

≈ 6.4 GB

Scale 0–8 GB, set by this estimate.

Estimate

Compute

≈ 1.23 FP16 TFLOPS peak

≈ 0.62 TFLOPS of real work

Scale 0–1.5 TFLOPS, set by this estimate.

Estimate

Bandwidth

≈ 255 GB/s peak

≈ 179 GB/s of real reads

Scale 0–300 GB/s, set by this estimate.

Memory breakdown

≈ 6.4 GB needed

Weights
≈ 4.6 GB
KV cache
≈ 1 GB
Activations
≈ 0.1 GB
Overhead
≈ 0.8 GB

Indicators

  • Fits a card, off
  • Exceeds every card, off
  • Bandwidth-bound, on
  • Compute-bound, off
  • Approximated, off
  • Mixture of experts, off
  • Dequantized compute, on
  • Checkpointing, off

Catalogue minimum: 4.93 GB — enough to load the model with a short context. This estimate is for your context and settings.

Find boards with at least ≈ 6.4 GB in the buyer's guide →Test this workload on my GPU →
What this assumes (12)
  • Weights take 4.85 bits each.
  • The KV cache stores 16 bits per value.
  • 0.5 GB is set aside for the GPU runtime and its libraries.
  • A further 5% is added for memory fragmentation and temporary buffers.
  • Reading the prompt holds 32 bytes of activations per token per hidden unit.
  • Prompts are read 512 tokens at a time.
  • Attention is costed with every sequence at its full context of 8K tokens.
  • Treated as a dense model: every parameter is used for every token.
  • A GPU is assumed to sustain 50% of its peak compute.
  • A GPU is assumed to sustain 70% of its peak memory bandwidth.
  • Quantized weights are expanded before each matrix multiply, so compute is counted at FP16.
  • Compute counts generating tokens only, not reading the prompt.