AI chip · AMD

AMD Instinct MI355X

Flagship of AMD's CDNA 4 MI350 series and the liquid-cooled counterpart to the air-cooled MI350X: 288 GB HBM3e, 8 TB/s, 256 compute units, native FP6/FP4, at 1400W. AMD's direct answer to NVIDIA B200/B300.

Market position

Flagship of AMD's CDNA 4 MI350 series (liquid-cooled vs the air-cooled MI350X): 288 GB HBM3e, 8 TB/s, 256 CUs, native FP6/FP4 (10.1 PFLOPS MXFP4 dense), at 1400W. AMD's direct answer to NVIDIA B200/B300.

Efficiency and power

How much work you get per watt and per dollar, and how much power a full rack draws.

Perf per watt: 3.57 FP8 TFLOPS/W
5,000 TFLOPS ÷ 1400 W = 3.57

What fits in 288 GB

Which open-source LLMs run on one AMD Instinct MI355X, by precision. Weights only: add roughly 15% headroom for real serving. If a model does not fit at FP16, try INT8 or INT4 (smaller quality trade-off than most people expect).

Model	Params	FP16	INT8	INT4
Llama 3.1 8B dense	8 B	16 GB ✓	8 GB ✓	4 GB ✓
Llama 3.1 70B dense	70 B	140 GB ✓	70 GB ✓	35 GB ✓
Llama 3.1 405B dense	405 B	810 GB ✗	405 GB ✗	203 GB ✓
Llama 3.3 70B dense	70 B	140 GB ✓	70 GB ✓	35 GB ✓
DeepSeek V3 MoE (671B total, 37B active per token)	671 B	1342 GB ✗	671 GB ✗	336 GB ✗
DeepSeek R1 MoE (671B total, 37B active per token)	671 B	1342 GB ✗	671 GB ✗	336 GB ✗
Qwen 2.5 7B dense	7 B	14 GB ✓	7 GB ✓	4 GB ✓
Qwen 2.5 72B dense	72 B	144 GB ✓	72 GB ✓	36 GB ✓
Mixtral 8x7B MoE (46.7B total, 12.9B active per token)	46.7 B	93 GB ✓	47 GB ✓	23 GB ✓
Mixtral 8x22B MoE (141B total, 39B active per token)	141 B	282 GB ✓	141 GB ✓	71 GB ✓
Gemma 2 27B dense	27 B	54 GB ✓	27 GB ✓	14 GB ✓
Command R+ dense	104 B	208 GB ✓	104 GB ✓	52 GB ✓
Kimi K2 MoE (1T total, 32B active per token)	1000 B	2000 GB ✗	1000 GB ✗	500 GB ✗

Math: FP16 = params × 2 bytes; INT8 = params × 1 byte; INT4 = params × 0.5 bytes. MoE models sum every expert (full weights on disk), not the per-token active subset.

Common questions

How much does AMD Instinct MI355X cost?

AMD Instinct MI355X doesn't have a public launch list price. Vendors like this one usually price through direct sales rather than a public sheet. See list price per TFLOP for chips that do publish.

How much memory does AMD Instinct MI355X have?

288 GB of HBM3e, running at 8,000 GB/s. Straight from the vendor datasheet. See chips with the most memory for context.

How much power does one AMD Instinct MI355X draw?

1400 W at the chip. A full server draws more once you add CPU, memory, networking and cooling: see the rack power number above. Compare to other chips on perf-per-watt.

Which open-source LLMs fit on one AMD Instinct MI355X?

Of 13 open-source LLMs we track, 9 fit at FP16, 9 at INT8, and 10 at INT4 (for example Llama 3.1 8B, Llama 3.1 70B and Llama 3.1 405B). Full table above with each model's memory need.

See every answer we publish →

Key facts

Class: Compute SoC (AI accelerator)
Designer: AMD
Safety-critical?: No (data-center inference / training)
Record as of: 2026-09-27

Specifications (10 fields, click to expand)

Straight from the vendor datasheet. Dense throughput shown first; sparse (2:4) numbers in parentheses where the vendor publishes them. Full datasheet linked below.

Process node: TSMC N3P
TDP: 1400 W
Memory: 288 GB HBM3e
Memory bandwidth: 8,000 GB/s
FP8 (dense): 5,000 TFLOPS
FP6 (dense): 10,100 TFLOPS
FP4 (dense): 10,100 TFLOPS (20,100 sparse)
Form factor: OAM
Announced: 2025-06-12
Released: 2025-10-01

Source: vendor datasheet

Generation

Predecessor:AMD Instinct MI350 seriesSuccessors:AMD Instinct MI400 Full AMD roadmap →

Foundry & process

Process node: TSMC N3P

Sources

AMD Instinct MI355XAMD
AMD releases details of 288GB MI355X acceleratorTechRadar

Adoption rows appear as we confirm each chip-in-robot pairing from a public source. See every chip we track for the full catalog or the AMD page.