macrostack

NVIDIA · Grace Blackwell · Layer 2

NVIDIA DGX Spark

Developers who want a coherent 128 GB memory space on a desk, at wall-socket power.

buy You can purchase this outright.

Specifications

Memory
128 GB unified LPDDR5X
Bandwidth
273 GB/s
Compute
GB10 Grace Blackwell superchip
Power
Roughly 170 W
Interconnect
ConnectX for pairing two units
Software
CUDA
Form factor
desktop
Workload
inference

Verified 2026-09-09. Fields reading “not published” are exactly that — we do not estimate a figure a vendor withholds.

The catch

273 GB/s is an order of magnitude below HBM. It loads big models; it does not serve them fast. Judge it as a development machine, not a server.

The economics

The cheapest legitimate route to running a 70B-class model locally with no cloud bill and no data leaving the building.

Cost per million tokens is the metric that decides most real purchases, and there is no neutral benchmark for it — every published figure comes from a company selling one side of the comparison. Read all of them, ours included, as claims rather than measurements.

The power question underneath this

A rack of frontier accelerators draws 120–200 kW against a 2026 average of about 27 kW, and the US grid interconnection queue exceeds 2,600 GW with waits approaching five years. Whether you can energise this part is now a harder question than whether you can buy it.

Layer 1 — Energy · The interconnection queue · Rack power density · Tokens per watt

Where you actually rent this

Choosing the part is the easy half. The same accelerator rents for wildly different money depending only on who you rent it from — the cheapest and dearest published on-demand price for an H100 sit 5.6× apart — and the provider, not the chip, is what decides whether you can leave later.

Layer 2.5 — Compute providers · The GPU cost calculator

Compared against

Related silicon

Want this whole layer as one table?

The accelerators on these pages as a single CSV — memory, bandwidth, compute, power, interconnect, software stack, availability, who each part is for and the catch — ready to sort, filter or load into a notebook.

Get the silicon table — free for research and evaluation

Four short lines and the download starts at once (CC-BY-NC-4.0, built from these pages the moment you ask). What you type is used only to answer the request and is never sold. Prefer Hugging Face? Request it there.

Using it inside a product, a client report or anything you sell? That needs a commercial licence.

Macrostack does not sell silicon and takes no commission at this layer — there is no affiliate programme for compute, which is exactly why nobody publishes a neutral comparison of it.

The Macrostack brief

New swaps, worth your inbox.

A short, occasional email when we add a high-intent alternative or ship a new head-to-head. No spam, no selling your address — unsubscribe in one click.