A100 80GB PCIe vs SXM4: Why the Used SXM Module Asks $8,575 Less (September 2026 Prices)
A100 80GB PCIe vs SXM4 used: 81 live asks (US median $18,500 vs $9,925, checked Sep 9, 2026), the datasheet spec diff, and three nvidia-smi checks to run first.
This guide is for: the infrastructure lead holding an SXM4 quote $8,000 a card under PCIe for eight used A100 80GBs, who needs to know whether that is a bargain or a paperweight.
A used A100 80GB SXM4 module is asking a median $9,925 from US sellers on eBay this week; the PCIe card with the same GPU inside is asking $18,500. Buy eight modules on that spread and you save $68,600 on paper, then discover a bare SXM4 module does not plug into any server you own, and the Q4 training run slips a quarter while eight modules sit in anti-static bags waiting for a chassis nobody budgeted.
The one-liner for your boss: an SXM4 module is a component; a PCIe card is a product. The gap between them is the price of the chassis you already have.
Same GA100 Die, Different Plumbing: What the Datasheet Separates
NVIDIA's A100 datasheet lists identical compute for both 80GB versions. What differs is power, interconnect, and the physical thing you bolt in.
| Spec | A100 80GB PCIe | A100 80GB SXM4 |
|---|---|---|
| FP64 / TF32 / FP16 Tensor | 9.7 / 156 / 312 TFLOPS | 9.7 / 156 / 312 TFLOPS |
| Memory | 80GB HBM2e | 80GB HBM2e |
| Memory bandwidth | 1,935 GB/s | 2,039 GB/s |
| Max TDP | 300 W | 400 W |
| Cooling | Passive; depends on chassis airflow | Baseboard airflow (HGX/DGX) |
| GPU-to-GPU | NVLink bridge kit, exactly 2 cards at 600 GB/s; beyond 2, PCIe Gen4 at 64 GB/s | NVLink 600 GB/s across 4, 8, or 16 GPUs inside an HGX A100 board or DGX A100 |
| Form factor | Full-height, full-length 10.5-inch dual-slot card, one CPU 8-pin, 1,170 g | Mezzanine module, no slot, no bracket |
| Identifiers | NVPN 699-21001-0230-xxx, PCI device ID 0x20B5 | Socketed; identified by baseboard, not slot |
| MIG | Seven 10GB slices | Seven 10GB slices |
Bandwidth differs by about 5 percent. Everything else in that table that differs is plumbing.
The verdict: own the servers, buy PCIe. Own an HGX A100 baseboard with empty sockets, buy SXM4. Never buy SXM4 modules before the baseboard is on your dock.
81 Live Asks, 55 Sellers, September 9: PCIe Is Nearly Double
We pulled every active eBay US-marketplace A100 listing on September 9, 2026, kept single-unit GPUs, and dropped brackets, heatsinks, multi-packs, the A100X converged accelerator, and two listings advertising faults. Eighty-one asks from 55 sellers survived; 33 ship from China. Asking prices, not sales. Last checked Sep 9, 2026.
| Variant | Asks (sellers) | US asks | US range | US median | Used/refurb median | New/open-box median |
|---|---|---|---|---|---|---|
| A100 80GB PCIe | 22 (17) | 15 | $14,950 to $24,999 | $18,500 | $17,350 (n=11) | $22,500 (n=11), max $31,196 from Canada |
| A100 80GB SXM4 | 9 (8) | 4 | $8,300 to $12,200 | $9,925 | n=6 incl. two Dell V40HX (500 W) from Poland at $13,803 and $14,070 | $16,999 (new, China) |
| A100 40GB PCIe | 34 (26) | 22 | $3,800 to $13,196 | $7,750 | $7,750 (n=19) | $9,080 (n=15) |
| A100 40GB SXM4 | 16 (15) | 1 | $3,355 (single used module) | $3,355 | 15 from China, almost all new stock: $4,049 to $8,000, median $4,575 |
The two excluded faults explain the tests below: an 80GB PCIe at $12,500 with "ECC Error" in the title, and a 40GB PCIe at $2,499 marked "Failed." Both were the cheapest in their class until we read the title.
The $8,575 Gap Is the Chassis, Not the Silicon
US median PCIe minus US median SXM4 is $8,575 per GPU, 46 percent, for the same die and memory. The only buyers for a bare SXM4 module already own an HGX A100 board with an empty socket; the PCIe card sells to anyone with a Gen4 x16 slot and airflow. On the short list, eight sockets times $8,575 is real money. Off it, the cheapest SXM4 module is the most expensive thing you will buy this year.
Three nvidia-smi Checks Before Money Moves
Have the seller run these on the exact unit and send raw output. A refusal is your answer.
- Identity.
lspci -nn | grep -i 10de. An 80GB PCIe card reports device 10de:20b5 (product brief, Table 1). Anything else is not the part in the listing. - Memory health.
nvidia-smi -q -d ROW_REMAPPER. Ampere remaps a memory row after a single uncorrectable ECC error, and each bank has a fixed number of reserve rows. Walk away if "Remapping Failure Occurred" reads Yes, or if the Bank Remap Availability Histogram shows any bank at None. "Pending: Yes" means the GPU needs a reset before the count can be trusted. - Power limit.
nvidia-smi -q -d POWER. Default and max limits should read 300 W on an 80GB PCIe card, 400 W on SXM4. A lower number was set by someone; ask who and why.
Walk away below $8,000 for an 80GB SXM4 or below $14,000 for an 80GB PCIe from a seller who will not send those logs. The lowest US asks this week were $8,300 and $14,950; the one US card under $14,950 advertised an ECC error.
PO Language You Can Paste
"Seller warrants that each GPU, under nvidia-smi -q -d ROW_REMAPPER, reports Remapping Failure Occurred: No, Pending: No, and zero uncorrectable remapped rows, and under nvidia-smi -q -d POWER reports a default power limit of 300 W (PCIe, NVPN 699-21001-0230-xxx) or 400 W (SXM4). Seller delivers raw output per serial number within 48 hours before shipment. Any unit failing any term is returnable within 30 days at Seller's freight cost."
What to Do This Week
- Run
nvidia-smi -q -d ROW_REMAPPERon the A100s you already own. Free, ten minutes, and you learn your fleet's reserve-row health before judging a seller's. - Count the sockets you are filling. Gen4 x16 slots with a spare CPU 8-pin: shop PCIe against the $14,950 to $24,999 US used asks above, with the middle of that market at $15,900 to $19,600. Empty HGX A100 sockets: shop SXM4 at $8,300 to $12,200.
- Put the PO clause above in the RFQ. Sellers who balk at logs before the sale will not answer the phone after it.
- Send part number and quantity to parts@caladansemi.com for a used NVIDIA A100 80GB, or a used H100 80GB if the workload has outgrown Ampere. We quote against the live comps you just read, within 4 business hours.
FAQ
"a100 80gb pcie vs sxm4 price" September 9, 2026, US eBay asks: median $18,500 for the 80GB PCIe card (15 listings), $9,925 for the 80GB SXM4 module (4 listings).
"a100 sxm4 used price" US asks for the 80GB SXM4 ran $8,300 to $12,200 this week. The 40GB SXM4 market is almost entirely Chinese new stock at $4,049 to $8,000.
"can you use a100 sxm4 without hgx" NVIDIA lists SXM4 A100s as available through HGX A100 server boards (4, 8, or 16 GPUs) and the DGX A100. The module is a socketed part, not a slot card; it does not go into a standard PCIe server slot.
"a100 pcie nvlink" A three-bridge NVLink kit connects exactly two 80GB PCIe cards at 600 GB/s. Past two cards, traffic falls back to PCIe Gen4 at 64 GB/s.
"a100 40gb vs 80gb used price" US asks: 40GB PCIe median $7,750 (22 listings) versus 80GB PCIe median $18,500 (15 listings). Every 40GB A100 runs 1,555 GB/s of memory bandwidth; the 80GB runs 1,935 (PCIe) or 2,039 GB/s (SXM4).
Related reading: Used H100 and A100 GPU Buying Guide | InfiniBand vs Ethernet for Used Data Center Builds
Related Parts
Caladan stocks used and refurbished parts referenced in this article — tested, inspected, and ready to ship.