Our take
Consider STBU500100 when a 500GB nominal limit is enough and the documented USB 3.0/USB 2.0 connection path fits the host. The optional FireWire 800 route depends on a separate adapter. Current power, operating-system support, seller package, and exact Amazon offer remain unverified.
A defined archive or travel copy within 500GB when USB 3.0 or documented USB 2.0 operation fits and the power arrangement can be checked.
Buyers who need more than 500GB, confirmed operation without an outlet, a verified current Amazon offer, current software support, or FireWire/Thunderbolt hardware included in the current package.
Pros & cons
What could work for you, and what to consider before buying.
What works in its favor
- Seagate maps the black 500GB configuration to exact model STBU500100.
- The sheet documents USB 3.0 use and backward compatibility with USB 2.0 hosts at USB 2.0 speeds.
- The USM design has a documented optional FireWire 800 adapter path for a legacy setup that can source the extra module.
What to weigh up
- The 500GB nominal capacity can be restrictive for a growing archive or multiple backup generations.
- The saved source does not establish bus power, an external-adapter requirement, or present seller cable contents.
- The historical model record does not prove current OS support, individual condition, or a current Amazon listing for ASIN B008422HVQ.
The key details
| Model covered | STBU500100; black; 500GB; USB 3.0 |
|---|---|
| Advertised capacity | 500GB nominal capacity; usable formatted space is not specified |
| Drive configuration | Black Seagate Backup Plus USM portable drive, model STBU500100 |
| Host connection | USB 3.0 interface with documented USB 2.0 host use at USB 2.0 speeds; optional FireWire 800 requires an additional adapter |
Performance figures are manufacturer claims. Source checked October 11, 2026. Regional models and included accessories can differ.
What the features mean for you
Will 500GB fit the archive you plan to keep?
The 2013 Seagate data sheet maps the Americas black 500GB configuration to model STBU500100. A 500GB nominal ceiling can fit a small set of documents, photos, or a travel copy when the files and expected growth fit below that limit. It is a constrained target for a backup that keeps several generations or a growing media library. Capacity is a hard boundary here: choose a larger verified model if one copy would fill the drive soon. The sheet notes formatted and other reserved space reduce usable capacity, but it gives no usable-space figure for a particular unit. This is a capacity fit, not a price or value claim. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 41–45 and 57–62; checked 2026-10-11.)
Can it connect to a USB 2.0-only host?
Seagate documents a USB 3.0 interface and states that a USB 3.0 port is needed for USB 3.0 operation; it also says the drive can work on a USB 2.0 port at USB 2.0 speeds. That makes this model relevant to a buyer with a mix of older and newer USB hosts. A USB 3.0 interface does not make a USB 2.0-only computer run at USB 3.0 speeds. The sheet cautions that compatibility varies by hardware and operating system; it provides no measured rate or task time for a particular machine. Check the computer's port and cable path before relying on the older drive with a specific host. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 33–35 and 60–61; checked 2026-10-11.)
Does the USM port make FireWire or Thunderbolt a direct connection?
The USM design lets its interface module be changed. The sheet describes the included USB 3.0 interface and says Thunderbolt or FireWire 800 requires an additional adapter. That creates a documented, accessory-dependent route to a legacy FireWire 800 host, not a promise that a current seller includes the adapter. The data sheet does not identify a Thunderbolt generation, so it cannot establish a Thunderbolt 2 connection. If FireWire is a must-have, verify the exact adapter model and whether it can still be sourced, along with the host-side cable needs. Choose a drive with the necessary interface in the current package if you cannot confirm those parts. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 17–20 and 36–40; checked 2026-10-11.)
Can it travel without an outlet?
Seagate calls this a portable drive, but the saved exact-model source does not state whether the USB configuration draws all required power from the host or needs another supply. Do not infer bus power from the compact product label. That uncertainty matters if the drive must work away from an outlet, through a hub, or with a low-power device. The source also does not establish which cable or interface module is included in a unit offered today. If power access is open, confirm the required supply with the seller before connecting it to the intended host. For a firm no-outlet requirement, prefer a model whose exact-source power arrangement is documented. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 22–28 and 36–40; checked 2026-10-11.)
Does the old compatibility list answer today's operating-system question?
The data sheet dates to 2013 and lists the Windows and Mac versions current to that document. Those version numbers do not verify support on a present-day operating system, and the saved work does not treat old software or warranty bundle terms as current benefits. Before using an older drive for backup, check its file system and the format and application requirements of the computer that will read it. If the unit contains files, make a separate copy before reformatting because formatting can erase stored data. Current host compatibility remains a question to verify for the exact machine, not an assumption from the model family. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 33–35 and 59–61; checked 2026-10-11.)
Does historical ASIN B008422HVQ identify the drive you can buy now?
The frozen candidate record carries historical ASIN B008422HVQ. Seagate's model table supports STBU500100 as the black 500GB USM configuration, but it does not connect that old ASIN to a current Amazon offer, seller, unit condition, or package. Other color and capacity choices use different model numbers, so check the exact code rather than relying on the Backup Plus name alone. Use the tagged model-search link, then confirm STBU500100, the black 500GB configuration, the installed interface module, and needed cable or power parts on the actual listing. No current price, stock, or ASIN mapping is claimed. ([Seagate data sheet](https://www.seagate.com/www-content/product-content/backup-plus-fam/backup-plus-portable-drive/en-us/docs/backup-plus-portable-usm-ds1756-3-1309us.pdf), lines 41–50; checked 2026-10-11.)
What else to compare
Before you buy
Will STBU500100 work with a USB 2.0 computer?
The data sheet says the USB 3.0 drive is backward compatible with USB 2.0 ports at USB 2.0 speeds. Compatibility with a particular host and operating system still needs checking.
Can it connect over FireWire?
The USM design has a documented FireWire 800 path through an additional adapter. That adapter is separate from the USB configuration, and present availability or seller inclusion is unknown.
Does it support Thunderbolt 2?
The sheet mentions a Thunderbolt adapter without naming its generation, so Thunderbolt 2 support is not established.
Can it run without an outlet?
The saved source does not establish bus-powered operation or an external-adapter requirement. Confirm the exact unit's power needs.
Is ASIN B008422HVQ a current exact Amazon listing?
No current exact-model mapping is verified. Use the tagged STBU500100 search and confirm the model, color, capacity, and included parts on the current offer.
Where can I check the current price?
Use the Amazon link for current offers. Check the exact model, seller, product condition, delivery, and return terms. This page does not display a live price or confirm stock.
Sources & review basis
We use the following manufacturer documentation for the product features above. Our suitability notes and buying advice are editorial judgments based on those features, not measured performance results.
- Seagate Backup Plus USM data sheet, DS1756.3 (2013) ↗ — checked October 11, 2026.
- Seagate Backup Plus USM data sheet DS1756.3 (2013), checked 2026-10-11: lines 17–20 describe the USB 3.0 design and optional FireWire 800 or Thunderbolt adapters; lines 33–40 list USB 2.0-compatible operation and the era-specific package; lines 41–45 map black 500GB STBU500100 and neighboring color variants. Historical operating-system, software, and warranty terms are not treated as current. ↗ — checked October 11, 2026.
The decision
Consider STBU500100 when a 500GB nominal limit is enough and the documented USB 3.0/USB 2.0 connection path fits the host. The optional FireWire 800 route depends on a separate adapter. Current power, operating-system support, seller package, and exact Amazon offer remain unverified.
Is it the right fit?
Check the exact model and today’s offers on Amazon.