PC Build to Run Gemma 4 31B Locally (Q4_K_M)

Written by Jakub Rusinowski · Last updated July 10, 2026

A complete parts list — GPU, motherboard, RAM and PSU — worked backward from Gemma 4 31B's VRAM requirement at Q4_K_M. Prices are 2026 street estimates and vary.

Requirements

GPU: AMD Radeon RX 7900 XT

AMD Radeon RX 7900 XT's 20 GB covers Gemma 4 31B at Q4_K_M (~20 GB needed), a tight fit — little headroom.

Check price on Amazon — AMD Radeon RX 7900 XT 20GB

Motherboard: ASUS TUF Gaming B650-PLUS WIFI

B650 (AM5) — pairs with the AMD Ryzen 7 7700; DDR5, dual PCIe 4.0 x16 (x8/x8) for multi-GPU, 4 DIMM slots to 256 GB.

Check price on Amazon — ASUS TUF Gaming B650-PLUS WIFI

RAM: Corsair Vengeance 64GB (2x32GB) DDR5-6000 C30 (AMD EXPO)

64 GB DDR5-6000 (2x32GB) meets Gemma 4 31B's 40 GB recommended system RAM.

Check price on Amazon — 64GB DDR5-5200 Kit (2x32GB)

PSU: Corsair RM650e (ATX 3.1)

650 W 80+ Gold covers AMD Radeon RX 7900 XT (315 W) + CPU 65 W with 30% headroom (~494 W required).

Check price on Amazon — Corsair RM650e (ATX 3.1)

Swap Alternatives

• GPU: AMD Radeon RX 7900 XTX — AMD Radeon RX 7900 XTX's 24 GB covers Gemma 4 31B at Q4_K_M (~20 GB needed), with headroom.
• GPU: NVIDIA GeForce RTX 3090 — NVIDIA GeForce RTX 3090's 24 GB covers Gemma 4 31B at Q4_K_M (~20 GB needed), with headroom.
• RAM: Corsair Vengeance 96GB (2x48GB) DDR5-5600 C40 — More headroom: 96 GB DDR5-5600.
• PSU: Corsair RM850e (ATX 3.1) — More headroom / future dual-GPU: 850 W 80+ Gold.

• The AMD Radeon RX 7900 XT is a tight fit at Q4_K_M — consider an upgrade alternative for KV-cache/context headroom.

FAQ

What GPU do I need to run Gemma 4 31B at Q4_K_M?

AMD Radeon RX 7900 XT's 20 GB covers Gemma 4 31B at Q4_K_M (~20 GB needed), a tight fit — little headroom.

How much VRAM does Gemma 4 31B need at Q4_K_M?

About 20 GB of VRAM plus 40 GB of system RAM.

What power supply does a AMD Radeon RX 7900 XT build need?

650 W 80+ Gold covers AMD Radeon RX 7900 XT (315 W) + CPU 65 W with 30% headroom (~494 W required).

How much does a Gemma 4 31B PC cost?

About $1,864 for a complete build (GPU, motherboard, RAM, PSU, CPU, case, SSD), at 2026 street-price estimates.

Gemma 4 31B at Other Quant Levels

• Gemma 4 31B at Q5_K_M
• Gemma 4 31B at Q8_0

Other Popular Build Targets

• Qwen 3 32B PC build
• Gemma 4 27B ⭐ PC build
• Kimi K2.6 PC build
• Qwen 3.7 35B-A3B PC build
• Qwen 3.6 35B-A3B PC build

Model & GPU

• Gemma 4 model page
• AMD Radeon RX 7900 XT review
• Can I run Gemma 4 on AMD Radeon RX 7900 XT?

More Ways to Build

• Budget-first build recommender
• Best GPU Buyer Guide 2026

← Budget-first build recommender | Gemma 4 model page | AMD Radeon RX 7900 XT review