NVIDIA RTX Spark: Windows 11 drivers reveal two versions with Blackwell GPU up to 6,144 CUDA cores

With the announcement of the RTX Spark platform, NVIDIA had hinted at the use of an Arm CPU with up to 20 cores alongside a GPU based on Blackwell architecture, but did not go into details about the graphics component. New information has emerged thanks to the release of the first native GeForce driver for Windows 11 on Arm, which provides a deeper insight into the expected configurations for the new SoC.

The driver in question is version GeForce 616.00, distributed as a Developer Preview and primarily intended for the Microsoft Surface RTX Spark Dev Box, the development system announced by Microsoft last June. Therefore, it is not a WHQL certified driver nor intended for future consumer notebooks, but a preliminary version aimed at developers.

Analyzing the Arm64 package of the driver, the file nv_surface_woa.inf was identified, which contains supported hardware identifiers and confirms the existence of two RTX Spark N1X configurations. The higher-end version integrates a Blackwell GPU with 6,144 CUDA cores, while the lower model features 5,120 CUDA cores.

The information confirms what had surfaced in previous months through rumors concerning the N1X 675 and N1X 650 variants. According to the driver, the more powerful configuration pairs the GPU with a 20-core Arm CPU and features 48 Streaming Multiprocessors (SM), while the lower version utilizes an 18-core CPU and 40 SM.

Both configurations instead share support for a maximum of 128 GB of unified LPDDR5X memory, a characteristic that represents one of the distinguishing elements of the platform, especially for workloads related to software development and artificial intelligence. Therefore, those choosing the less powerful model will not have to forgo the maximum available memory capacity.

The driver also includes references to a generic "NVIDIA Desktop Device," along with several identifiers related to the NPU based on the company's Deep Learning Accelerator architecture. The desktop device could correspond to the same Surface RTX Spark Dev Box or to another compact system based on the RTX Spark platform, but the driver does not provide further details.

The Surface RTX Spark Dev Box has been presented with a maximum consumption of 100 W and a configuration that reaches up to 128 GB of unified memory. At the same time, NVIDIA and its partners are also preparing notebooks based on the same platform, including models like Surface Laptop Ultra and Lenovo Yoga Pro 9n.

The number of CUDA cores, however, does not alone represent a direct indicator of performance. The 6,144 CUDA core configuration coincides, for example, with that of the GeForce RTX 5070 desktop and the RTX 3080 Laptop, while the 5,120 CUDA cores of the lower model refer to the configuration of the RTX 3070 Laptop GPU. The architectural differences of the SoC, the power budget, and the integration with unified memory make a direct comparison with traditional discrete GPUs somewhat insignificant.

Initial demonstrations of the platform have nonetheless shown smooth execution of titles like Alan Wake 2 and PRAGMATA, even with active path tracing, suggesting that RTX Spark may offer interesting performance while adopting a fundamentally different approach compared to dedicated graphics cards. Of course, with extensive use of DLSS.

In addition to the two chips essentially confirmed by the drivers, there are rumors that we will see minor versions, part of the offering defined as "N1". Unconfirmed rumors indicate a configuration with 12 Arm cores and 20 SM, with a thermal budget of up to 45 W and a maximum of 64 GB of unified memory. Another variant would foresee 10 cores and 16 SM, still within the same TDP and with the same memory allocation. Of course, we will know more only in autumn as the launch approaches.