DGX Spark GB10 Grace Blackwell, 128GB vs AMD Radeon AI PRO R9700, 32GB for local AI
The DGX Spark, 128GB holds 40 of the 49 current models here, and the Radeon AI PRO R9700, 32GB holds 33. The Radeon AI PRO R9700, 32GB costs $3,400 less, though the Radeon AI PRO R9700, 32GB is priced as the card alone, without the PC around it. On Qwen3.8 27B, the strongest model both hold, the Radeon AI PRO R9700, 32GB is about 2.7× faster: 30 tok/s against 11, both estimated from memory bandwidth. The Radeon AI PRO R9700, 32GB pays for itself sooner, in 84 years against 346 years at 500k tokens a day.
| DGX Spark GB10 Grace Blackwell, 128GB | AMD Radeon AI PRO R9700, 32GB | |
|---|---|---|
| Price | $4,699 | $1,299card only |
| Memory | 128 GB | 32 GB |
| Usable by the GPU | 119.5 GB | 31 GB |
| Memory bandwidth | 273 GB/s | 640 GB/s |
| Power under load | 150 W | 300 W |
| Models that fit | 40 | 33 |
| Best model it runs | Qwen3.8 27B | Qwen3.8 27B |
| Speed on that model | 11 tok/s estimated | 30 tok/s estimated |
| Pay-back on that model | Pays back in 346 years | Pays back in 84 years |
Run the numbers on the DGX Spark GB10 Grace Blackwell, 128GB · or the AMD Radeon AI PRO R9700, 32GB
How much use it takes to pay back
Everything above is at 500k tokens a day. Pay-back moves with how much you actually run, so here are both machines on Qwen3.8 27B, the strongest model both hold, at the five levels of use the calculator names. The AMD Radeon AI PRO R9700, 32GB pays back sooner at every level of use, so this is not a choice that turns on how hard you work it.
| A day's use | DGX Spark GB10 Grace Blackwell, 128GB | AMD Radeon AI PRO R9700, 32GB |
|---|---|---|
| 50ka few chats a day | 3,456 years | 836 years |
| 200klight assistant use | 864 years | 209 years |
| 1Ma moderate coding-assistant day | 173 years | 42 years |
| 4Mheavy coding with an agent | 43 years | 10 years |
| 20Magents running most of the day | 11 yearsits ceiling | 2.1 years |
On Qwen3.8 27B the DGX Spark GB10 Grace Blackwell, 128GB generates at most 15.2M tokens a day, so its figure at 20M tokens a day is for the most it can do, not for the whole of what was asked.
Run the DGX Spark GB10 Grace Blackwell, 128GB at 20M tokens a day · or the AMD Radeon AI PRO R9700, 32GB
What the extra memory buys
The DGX Spark GB10 Grace Blackwell, 128GB holds 7 models the AMD Radeon AI PRO R9700, 32GB cannot at 32k of context. The strongest of them are what the difference in memory actually buys.
| Model | Weights | Needs at 32k | On the DGX Spark GB10 Grace Blackwell, 128GB |
|---|---|---|---|
| Ling 3.0 flashHaiku-class | 78 GB | 78 GB | 51 tok/s estimated |
| Qwen3.5 122B-A10BHaiku-class | 78 GB | 79 GB | 25 tok/s estimated |
| gpt-oss-120bBelow every hosted tier | 63 GB | 65 GB | 41 tok/s measured |
| Mistral Small 4 (119B-2603)Below every hosted tier | 74 GB | 75 GB | 40 tok/s estimated |
| Qwen3-Coder NextBelow every hosted tier | 48 GB | 49 GB | 68 tok/s estimated |
| Devstral 2 123BBelow every hosted tier | 75 GB | 87 GB | 2.4 tok/s estimated |
1 more, on the DGX Spark GB10 Grace Blackwell, 128GB page.
The extra memory buys context as well. Of the 33 current models both machines hold at 32k, 11 run to a longer window on the DGX Spark GB10 Grace Blackwell, 128GB: the weights are a fixed size and the KV cache is not, so what the weights leave spare is what a longer context grows into. Nanbeige4.3 33B reaches 256k there against 32k on the AMD Radeon AI PRO R9700, 32GB, each the longest window the calculator offers that the machine still holds it at.
The DGX Spark, 128GB is also head to head with another computer: Mac mini M5 Pro, 24GB · Mac Studio M5 Max, 128GB · GMKtec EVO-X2, 128GB · MacBook Air M5 (15-inch), 16GB · MacBook Pro M5 Pro (16-inch), 64GB · Corsair AI Workstation 300, 128GB. With a graphics card: RTX PRO 6000 Blackwell, 96GB.
The Radeon AI PRO R9700, 32GB is also head to head with another card: RTX PRO 6000 Blackwell, 96GB · GeForce RTX 5090, 32GB · GeForce RTX 4090, 24GB · GeForce RTX 3090, 24GB · GeForce RTX 4080, 16GB · GeForce RTX 3060, 12GB. With a complete computer: Mac mini M5 Pro, 24GB · Mac Studio M5 Max, 128GB · GMKtec EVO-X2, 128GB · MacBook Air M5 (15-inch), 16GB · MacBook Pro M5 Pro (16-inch), 64GB · Mac mini M6, 32GB.
The assumptions behind both columns
Both columns use the same usage: 500k tokens a day at 15:1 input to output, 32k of context, $0.17 per kWh, and today's API prices held flat. Speeds marked estimated are worked out from memory bandwidth rather than measured, and pay-back scales with them. The Radeon AI PRO R9700, 32GB is priced as the card alone, so add the PC around it before comparing it with a complete computer. All seven cards here are ranked by what each one holds. Change any of it in the calculator.
More head to head: everything the DGX Spark GB10 Grace Blackwell, 128GB runs · everything the AMD Radeon AI PRO R9700, 32GB runs · every other match-up · the quickest pay-back at each level of use · every model against the frontier