Seagate · Enterprise
ST1200MM0129 is Seagate Enterprise 1.2TB SAS-12G. 2 of its 5 segments are defined in Seagate's published documentation and decoded below; the rest are not publicly documented and are marked as such. No live listings right now - the reference material below still applies.
| Segment | What it means | Source |
|---|---|---|
| ST | Seagate product prefix. | Seagate |
| 1200 | Capacity field. 1200 denotes 1.2TB of formatted capacity. | Seagate |
| MM | Seagate does not publicly document this segment. | not documented |
| 012 | Seagate does not publicly document this segment. | not documented |
| 9 | Seagate does not publicly document this segment. | not documented |
We decode only what the manufacturer documents. There is a large body of community knowledge about the undocumented segments above, much of it probably right, and none of it published by Seagate - so it does not appear in this table. A reading nobody can check does not belong in a column headed “what it means”. Grammar reference: Seagate - product part-number and model-number decoding.
ST1200MM0129 is Seagate Enterprise, a 1.2TB hard drive on SAS-12G. Being a SAS device, it needs a SAS host bus adapter or backplane - it will not run from a motherboard SATA port, though a SATA drive will run on a SAS controller.
We hold no live listing against this exact part number at the moment. We document no sibling variants for this part number.
| Manufacturer | Seagate |
| Family | Enterprise |
| Capacity | 1.2TB |
| Interface | SAS-12G |
| Product class | HDD |
No live listings for ST1200MM0129 right now. We are not going to fill this space with something else and call it a match. The decode, specifications and sibling table above are the reference answer for this part number and remain accurate whether or not anyone is selling one today. If you need the capacity rather than this specific part, the alternatives below are what is actually buyable.
A manufacturer part number does not imply a manufacturer warranty, and this is where part-number buyers lose the most money. OEM stock, integrator pulls and gray-market units all reach the market under the maker's own numbering. Retailers selling them sometimes state plainly that the manufacturer warranty is none; others simply do not mention it, which is not the same as it being covered.
Coverage attaches to the individual unit and its serial number, not to the part number. That means the only reliable answer comes from the manufacturer, about the specific drive you are being sold.
Ask the seller for the serial number before purchase, then enter it in Seagate warranty checker. We link the tool rather than showing a result here, because the answer depends on the individual drive and only Seagate can give it.
A seller warranty is a different promise from a different company. What each warranty tier actually covers · Verify on arrival
4 in-stock listings · same capacity, any part number · ranked by live cost per tb, refreshed every few hours
| Drive | Capacity | Interface | Recording | Condition | $/TB | Price | |
|---|---|---|---|---|---|---|---|
| HP 781578-001 1.2TB 12G SAS 10K 781578-001 | 1.2TB | SAS-12G | CMR | NEW | $33.33 | $40 | Buy |
| HGST 1.2TB 10K SAS 12G 2.5 HUC101212CSS600 | 1.2TB | SAS-12G | CMR | NEW | $44.17 | $53 | Buy |
| HP 781518-B21 1.2TB 12G SAS 10K 781518-B21 | 1.2TB | SAS-12G | CMR | REFURB | $45.83 | $55 | Buy |
| HP 781578-001 1.2TB 12G SAS 10K SFF 781578-001 | 1.2TB | SAS-12G | CMR | REFURB | $46.67 | $56 | Buy |
Every 1.2TB drive we track, ranked by cost per terabyte.
ST1200MM0129 is Seagate Enterprise 1.2TB SAS-12G. 2 of its 5 segments are defined in Seagate's own published documentation - the decode table on this page shows each one with the document that defines it. The remaining segments are not publicly documented, and we say so rather than repeating a community guess as fact.
Not necessarily, and the part number cannot tell you. Coverage depends on how the individual unit entered the market and whether it was registered, not on its model designation. OEM and gray-market stock reaches the market under manufacturer part numbers regularly and frequently carries no manufacturer warranty at all - some retailers print exactly that on the listing. Check the specific serial with Seagate's own tool, linked in the warranty section on this page.
We hold no live listing for this part number right now. That is the honest state rather than a broken page - this remains the reference answer for what ST1200MM0129 is, how it decodes and which siblings it is confused with. The alternatives section below shows what is currently buyable at the same capacity.
Because more than one organisation names it. The manufacturer assigns a model number describing the product; a server vendor buying it in volume assigns its own spare-part number for its service catalogue; distributors sometimes add another. All identify the same physical drive, which is why one number returns listings that look like a different product. Our part number index explains the pattern per vendor.