Lenovo ThinkSystem SR680a V4 vs QCT QuantaGrid D75L-3U
Both are built on the NVIDIA HGX B300 8-GPU baseboard, so their accelerator performance is identical rather than merely similar. The choice between them is chassis, cooling, expansion and supplier, not FLOPS.
What actually differs
| Specification | Lenovo ThinkSystem SR680a V4 | QCT QuantaGrid D75L-3U |
|---|---|---|
| Vendor | Lenovo | QCT |
| Part number | 7DMK | D75L-3U |
| Form factor | rack | rack |
| Released | — | — |
| Accelerator | 8x B300 | 8x B300 |
| Aggregate memory | — | 2.3 TB |
| Aggregate bandwidth | — | — |
| System power | — | — |
| Interconnect | One NVIDIA HGX B300 SXM baseboard, which Lenovo pairs with fast interconnects between GPUs, CPUs and networking | One NVIDIA HGX B300 8-GPU baseboard with fifth-generation NVLink at 1.8 TB/s; eight onboard ConnectX-8 SuperNICs at up to 800Gb/s for east-west traffic, with up to three further NICs for north-south |
Rows shown in grey are identical between the two.
Lenovo ThinkSystem SR680a V4
Lenovo's Blackwell Ultra machine, an 8U server developed in-house around eight NVIDIA HGX B300 SXM GPUs and two Intel Xeon 6700P processors reaching 86 cores at up to 350 W. Notably it is designed for air cooling, where most B300 machines in this catalogue are liquid cooled or need direct-to-chip plumbing, and it carries that with 21 hot-swap fans, six at the front for CPUs and memory and fifteen at the rear for drives and the GPU subsystem. Power is six or eight hot-swap supplies, either 3,200 W AC or 3,800 W high-voltage AC or DC, in N+1 or N+N redundancy. The chassis is 447 by 351 by 924 mm at up to 124.7 kg, the heaviest of Lenovo's 8U accelerator servers. Lenovo publishes no system power draw, no accelerator memory total and no system throughput figure; its per-GPU B300 table matches NVIDIA's own specification for the baseboard, which is linked here.
Vendor product pageQCT QuantaGrid D75L-3U
QCT's density play: the same NVIDIA HGX B300 8-GPU baseboard as its 10U sibling, compressed into 3U by liquid cooling and designed for the NVIDIA MGX rack rather than a standalone chassis. It takes power from a 1400A busbar and rack power shelves instead of its own supplies, which is why no power figure appears here at all, and supports DC-SCM. Fifth-generation NVLink runs at 1.8 TB/s, and eight onboard ConnectX-8 SuperNICs handle east-west traffic at up to 800Gb/s. Hosting is two Intel Xeon 6700 P-core processors at up to 350 W. QCT states 2.3 TB of HBM3e per system, which is eight B300 modules at 288 GB apiece; note NVIDIA quotes 2.1 TB for the same baseboard, and this entry keeps QCT's figure since QCT is the one publishing it. No throughput figure is given for this model.
Vendor product page