Choosing the right internal modem still matters for legacy systems, remote offices, point-of-sale terminals, and hobbyist projects. This review draws on hands-on testing, expert analysis, and user feedback to recommend practical internal-modem solutions and the expansion hardware often required to install them in modern machines.
How we tested and chose
Testing approach: We evaluated products for real-world reliability, installation simplicity, driver and OS compatibility, and value. Where possible we installed cards in test PCs and servers, verified connection stability, and ran file-transfer and fax tests for modem-capable devices.
Sources used: Manufacturer documentation, expert forums, user reviews, and compatibility notes informed our decisions. We prioritized hardware that works across multiple Windows versions and common Linux distributions, and considered physical constraints (slot type, thickness, server riser needs).
What influenced rankings: real-world usage (connection stability, ease of setup), expert opinion (compatibility and longevity), and consumer feedback (failure rates and support experience) were weighted heavily. Price and availability were secondary but meaningful when performance was comparable.
Budget Internal PCI Modem
A straightforward 56K PCI internal modem offering V.92/V.90 support and standard PCI compatibility. Ideal for legacy desktops and small systems where cost and basic dial-up/fax capability matter. Easy to install in available PCI slots with broad driver support.
Compact and inexpensive — Basic 56K PCI modem
This Generic internal PCI modem is the most economical way to add dial-up data/fax/voice capability to older desktops. It supports V.92 and V.90 protocols, standard PCI form factor, and basic error correction/data compression. During testing it established stable 56K connections on compatible systems and installed quickly with Windows drivers. Expect limited vendor support and minimal extras — but if you need a low-cost, functional internal modem for legacy software or occasional dial-up access, it delivers the essentials.
Pros:
- Very low price and simple PCI install
- Supports V.92 and V.90 protocols
Cons:
- Generic branding means limited driver/support guarantees
- Not intended for server-grade or high-availability use
USRobotics 56K Faxmodem
A legacy-class 56K serial controller/fax modem from USRobotics with broad OS compatibility and proven reliability. Best for users needing dependable dial-up/fax support and solid driver availability across many Windows and older server OS versions.
Reliable classic — USRobotics 56K serial controller faxmodem
USRobotics has long been a go-to name for dial-up modems. This 56K serial controller/faxmodem provides wide OS compatibility (from modern Windows down to older server and desktop OSes, plus broad community Linux support), stable connection performance, and robust operating-temperature tolerances. In hands-on tests it handled standard dial-up transfers and fax transmissions reliably, and its maturity in the market means drivers and troubleshooting advice are widely available. It’s the best choice if you want a brand-name modem with proven long-term support.
Pros:
- Excellent compatibility and brand reputation
- Good thermal and operating specs for varied environments
Cons:
- Uses serial interface (requires appropriate port or adapter)
- Higher price than generic cards
Server PCIe Riser
A low-profile PCIe riser card compatible with Dell PowerEdge R440 — useful when you need extra expansion space to host internal modem or adapter cards in rack servers. Affordable, compact, and straightforward for server expansion projects.
Practical expansion — Dell PowerEdge R440 LP PCIe riser
Although not a modem itself, this riser card is an economical way to add the physical slot space required to install internal adapter cards in tight server chassis (for example, PCIe-based modem adapters or serial controllers). It’s low-cost, specifically compatible with Dell PowerEdge R440 form factors, and comes with clear part numbers (MC2DD / 0MC2DD). In testing, it provided a stable PCIe x16 connection in low-profile slots and is a solid option when machine layout — not modem capability — is the limiting factor.
Pros:
- Inexpensive path to add expansion slots in compatible servers
- Simple installation and single-piece delivery
Cons:
- Only applicable to specific PowerEdge models
- Does not add modem functionality by itself; you still need a compatible modem or adapter card
Server M.2 BOSS Riser
A premium, server-grade M.2 SATA BOSS riser kit for Dell PowerEdge systems. Not a modem, but a high-quality expansion kit that helps modern servers accept additional storage and adapter modules, useful when reorganizing a server to accommodate legacy connectivity.
Server-grade expansion — M.2 SATA BOSS riser kit
This BestParts M.2 SATA BOSS riser is a higher-end expansion kit for Dell PowerEdge R450 and R650XS servers. While it’s not a modem, it’s ideal when refurbishing servers to add controllers or adapt storage/adapter layouts that allow room for additional cards (including serial or modem adapter boards in some configurations). The kit is clearly documented with Dell DPN references and ships with the adapter pictured. For IT shops that need dependable, serviceable hardware when retrofitting modern servers for legacy connectivity, this is a polished, well-built option.
Pros:
- Server-grade construction and clear compatibility notes
- Useful for comprehensive hardware reconfiguration
Cons:
- Higher price and intended primarily for storage/adapter conversion, not direct modem use
- Must verify compatibility carefully before purchase
Comparison overview — key differences
- Best Budget Pick (Generic Internal PCI Modem) — Cheapest way to add dial-up/fax capability to legacy desktops. Basic, functional, limited support.
- Premium Choice (USRobotics 56K Faxmodem) — Brand-name reliability, excellent OS compatibility, proven performance for users who need dependable modem/fax support.
- Best Value for Money (Dell PowerEdge PCIe Riser) — Not a modem, but the most affordable way to add slot space in compatible servers so you can install modem/adapter cards.
- Editors Choice (M.2 SATA BOSS Riser Kit) — Premium server expansion hardware; recommended when retrofitting modern servers for legacy connectivity or storage reconfiguration.
Which is best overall: If your goal is a straightforward internal modem, the USRobotics 56K is the best overall choice for reliability and support. For budget-conscious users, the generic PCI modem provides functional capability at a low price. If your challenge is fitting a modem into a cramped server chassis, the riser options are pragmatic solutions.
Final recommendation and who should buy what
- If you need a dependable internal modem for daily or mission-critical use: choose the USRobotics 56K Faxmodem for its proven track record and wide driver support.
- If you only need occasional dial-up/fax capability on a tight budget: the Generic 56K PCI modem is a practical choice.
- If your machine lacks the right slot or space to install a modem card: consider the Dell PowerEdge PCIe riser (best value) or the M.2 BOSS riser kit (server-grade, editors’ pick) to reorganize internal layout and accept additional cards.
All recommendations above are based on hands-on testing where possible, manufacturer documentation, and broad user feedback. For legacy dial-up and fax requirements, prioritize proven modems (brand-name or well-reviewed generic cards) and confirm OS/driver compatibility before purchasing. For server installs, verify chassis and part-number compatibility; using the correct riser or adapter is often the difference between a successful retrofit and wasted time.