Supermicro GPU A+ Server AS-8126GS-NB3RT NVIDIA HGX B300 NVL8

Blackwell Ultra is the first GPU generation designed after the industry learned what reasoning models cost to serve. The B200 answered the training question; the B300 answers the inference-era question that followed it, and the changes are specific rather than cosmetic. This Supermicro A+ platform is the 8-GPU node those changes ship in. The GPU complex. Eight NVIDIA Blackwell Ultra B300 SXM GPUs mount to the HGX B300 NVL8 baseboard, each carrying 288GB of HBM3e, 60 percent more than the B200, pooling 2,304GB across the node. Fifth-generation NVLink joins every GPU at 1.8 TB/s through NVSwitch in full mesh. NVIDIA rates the B300's dense FP4 throughput at 1.5 times the B200, an uplift concentrated exactly where high-volume serving lives, and the second-generation Transformer Engine's micro-tensor scaling is what makes four-bit inference hold production accuracy. The memory bandwidth per GPU remains in the 8 TB/s class; the capacity is the headline, because capacity is what reasoning workloads exhaust first. Why capacity defines the reasoning era. A model that thinks before answering generates internal tokens, and every one of them occupies KV cache for the duration of the response. Long reasoning traces, extended context windows, and high-concurrency serving multiply that footprint together. On smaller nodes the result is offloading, batch-size collapse, or both, and serving margins go with them. A 2.3TB node holds frontier-scale weights and the caches they generate simultaneously, which is the difference between a model that fits and a deployment that profits. The integrated fabric, and what it changes about the chassis. The HGX B300 NVL8 baseboard carries its own networking: eight OSFP ports at 800 Gb/s, one per GPU, double the per-port rate of the prior generation's add-in adapters. This is why the spec sheet shows only two PCIe 5.0 expansion slots where B200-class systems carried a dozen; the twelve slots existed to hold NICs, and those NICs now live on the baseboard. For multi-node deployments the consequence is a cleaner build, a faster fabric, and GPUDirect RDMA topology guaranteed by design rather than assembled per order. The two remaining slots carry storage and management networking. The Supermicro host. Dual AMD EPYC 9005 or 9004 series processors, up to 192 cores per socket on the 9005 line, feed the preprocessing, tokenization, and data-loading work eight GPUs of this class demand. Twenty-four DDR5 modules at 6400 MT/s populate one per channel across twelve channels per processor and scale to 6TB, holding the full-bandwidth layout while sitting far above the GPU pool, the sizing rule this catalog teaches, cleared with room to spare. Eight front hot-swap E1.S NVMe bays keep datasets on-node, and six 6600W Titanium-level supplies in a redundant arrangement define a power envelope that is unambiguous about what this is: a data center machine at the top of the air-cooled single-node class. The decision against the HGX B200 in this catalog. The Gigabyte B200 node delivers 1.4TB and the same NVLink generation, and for training programs and serving fleets working within that memory envelope it remains the rational Blackwell buy. The B300 earns its position in three situations: reasoning and long-context inference fleets where KV cache depth decides batch size and therefore unit economics, deployments serving frontier-scale models that press past 1.4TB, and operators standardizing on the integrated 800G fabric for multi-node growth. Below those thresholds, the B200 wins on economics; at them, the B300 is the only node that fits. The decision against rack-scale. Above this machine sit the GB200 and GB300 class systems, where 72 GPUs share one NVLink domain under liquid cooling and facility engineering to match. The boundary is unchanged: if training parallelism genuinely needs more than eight GPUs in a single coherent domain, rack-scale is the answer. For everything that fits eight Blackwell Ultra GPUs, which now includes serving the largest deployed models, this node delivers the generation without the facility project and scales outward across its built-in 800G fabric. Export compliance and ordering. Blackwell-class accelerators are subject to US export controls, and MillionMiner confirms destination eligibility as part of every quote. Each system is configured to order, tested, and shipped worldwide DDP with duties and customs handled. Deployment planning and hosting in MillionMiner's own data centers are available for teams that prefer not to provision rack power at this scale on-site.