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October 7, 2026No. 158
Home / Will it run? / Phi-3.5 mini Instruct / Radeon RX 9070 XT
Radeon RX 9070 XT ยท 16GB GDDR6

Can the Radeon RX 9070 XT run Phi-3.5 mini Instruct?

Fits comfortably at Q4_K_M.

Phi-3.5 mini Instruct is 3.82B parameters. At Q4_K_M the weights are about 2.1 GiB; with the 1.5 GiB runtime reserve that is 3.6 GiB against the card's 16GB, leaving about 12.4 GiB for context.

All three quants

16GB card
QuantWeightsWith reserveVerdictHeadroom
Q4_K_Mthe everyday quant2.1 GiB3.6 GiBFits comfortably12.4 GiB
Q8_0near-lossless3.8 GiB5.3 GiBFits comfortably10.7 GiB
FP16full weights7.1 GiB8.6 GiBFits comfortably7.4 GiB

Verdict rules: fits comfortably when weights plus reserve sit within 85% of VRAM; tight when they fit with little left for context; CPU offload when they exceed VRAM by up to 2x (runs, slowly, with layers in system RAM); no beyond that. The KV cache per token depends on the model's architecture and is not modelled here.

The numbers for this pairing

At Q4_K_M the weights take about 2.1 GiB; with the 1.5 GiB we set aside for the runtime that is 3.6 of the card's 16 GB, leaving about 12.4 GB for the context cache.

The highest-quality version that fits entirely in memory is FP16 (full quality).

The cheapest card on our list that runs it comfortably at Q4 is the Arc B570 at about $260, against about $810 for this card.

At about $810, this card costs roughly $51 per GB of VRAM.

Running it at its full 304 W board power for 4 hours a day would use about 36 kWh a month, about $6.71 at the US average residential rate of 18.4 cents per kWh (2026-05); real use sits below that ceiling.

Prices are the lowest current listings our tracker saw on Oct 7, 2026, since averages include premium variants; launch prices are marked where we have no listing.

Good match. Get the card.

The Radeon RX 9070 XT clears Phi-3.5 mini Instruct at Q4_K_M and at Q8_0. Live listings below; this page was rebuilt 2026-10-07.

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About the model

Phi-3.5 mini Instruct by Microsoft: 131,072-token native context, text, released 2024 under the MIT. Model card →

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