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Can I run Mixtral 8x7B (MoE) on NVIDIA RTX 4060 Ti 16GB?

Not comfortably: Mixtral 8x7B (MoE) only runs on NVIDIA RTX 4060 Ti 16GB with Q2_K by offloading part of the model to system RAM, which is much slower (often a few tokens/s). Smaller models or lower quantisations fit entirely in memory.

Memory by quantisation (8,192-token context)

QuantisationMemoryVerdictEst. speed
F16Unquantized reference89.6 GiBDoes not fitโ€”
Q8_0Near-lossless48.8 GiBDoes not fitโ€”
Q6_KVery close to F1638.3 GiBDoes not fitโ€”
Q5_K_MGreat quality/size33.5 GiBNeeds CPU offloadโ€”
Q4_K_MBest default for most29.0 GiBNeeds CPU offloadโ€”
IQ4_XSSmaller 4-bit (imatrix)25.7 GiBNeeds CPU offloadโ€”
Q3_K_MNoticeable loss23.9 GiBNeeds CPU offloadโ€”
Q2_KLast resort; big loss20.8 GiBNeeds CPU offloadโ€”

NVIDIA RTX 4060 Ti 16GB offers about 16 GiB of memory (92% usable for a model) at 288 GB/s. Speed is a bandwidth-bound estimate of single-stream generation at 65% efficiency; real results vary by runtime, drivers and settings, so measure on your machine.

How this is calculated

Weights โ‰ˆ parameters ร— bits per weight รท 8. KV cache โ‰ˆ 2 ร— 32 layers ร— 8 KV heads ร— 128 head dim ร— 2 bytes per token. Decode speed โ‰ˆ efficiency ร— memory bandwidth รท bytes read per token (this is a mixture-of-experts model, so only the active parameters are read, but all of them must fit in memory). Learn the maths in VRAM math and memory bandwidth, or try the VRAM calculator.

Running slowly or out of memory? See CUDA out of memory and the quantisation lesson.