StarTech ST124PRO 4-Port High-Resolution VGA Video Splitter

Overview

The StarTech ST124PRO is a 4-port VGA distribution amplifier designed for installations that need to drive a single video source to multiple displays simultaneously — without signal degradation. With a 350 MHz video bandwidth and support for resolutions up to 2048x1536 at 80Hz, this unit handles everything from standard 1080p control room monitors to high-resolution QXGA displays. If you're running a training room, digital signage loop, or security monitoring station where one PC or DVR needs to feed four screens from a single VGA output, the ST124PRO is engineered for exactly that use case.

It draws just 5 watts from a universal 100–240V AC input — making it compatible with any commercial power environment globally — and delivers a clean 5V DC output at 1A to the internal signal circuitry. FCC Part 15 Class A and CE Mark approvals confirm it meets commercial electromagnetic emissions standards, which matters in environments with sensitive RF equipment nearby. For a broader look at the StarTech product line, including KVM switches and connectivity hardware, the brand offers a wide range of signal distribution solutions suited to AV and control room deployments.

Key Features

• 350 MHz Video Bandwidth: This isn't a passive splitter — active signal amplification at 350 MHz means each of the four outputs receives a clean, boosted signal rather than a split-and-degraded one. At lower bandwidths, high-res signals soften noticeably at the edges of the display; 350 MHz keeps the image sharp even on QXGA panels.
• 2048x1536 @ 80Hz Maximum Resolution: QXGA support means the ST124PRO isn't limited to 1080p environments. Radiological workstations, engineering review stations, or legacy QXGA monitors used in control rooms will all sync cleanly at native resolution — no forced downscaling that blurs fine detail.
• 4 Independent VGA Outputs: One source, four displays, simultaneously. All four ports receive an identical, amplified signal — useful for briefing rooms, training labs, or any display wall where consistency across screens is required.
• 210-Foot Maximum Cable Run: At 210 ft per output, the ST124PRO can push signal to displays in adjacent rooms or across a large open floor without a second amplifier stage. This range covers most single-floor commercial deployments without daisy-chaining additional hardware. Plan cable routing to respect this limit — exceeding it risks visible ghosting or sync loss, especially at higher resolutions.
• Universal AC Input (100–240V, 0.3A): The onboard power supply accepts any mains voltage worldwide. This matters for international deployments or government facilities that run mixed power infrastructure — no step-down transformer required.
• Compact Form Factor (7.2 x 3.1 x 0.8 in, 13.8 oz): At under an inch tall, the ST124PRO sits flat on a equipment shelf or mounts easily in a cable management tray without consuming rack space. Its 13.8 oz weight means no dedicated mounting hardware is needed in most desktop deployments.
• 0–40°C Operating Temperature: Rated for standard commercial indoor environments. This is an office and control room unit — not rated for unheated equipment closets or outdoor enclosures. Plan accordingly if the installation site runs hot or cold beyond this band.
• FCC Part 15 Class A / CE Mark: Meets commercial (not just residential) electromagnetic compatibility requirements. Class A certification indicates it's designed for use in commercial, industrial, and business environments where stricter RF emissions limits apply.

Integration and Compatibility

The ST124PRO works with any VGA video source — PCs, DVRs, media players, or any device with a standard HD-15 VGA output. It distributes signal to up to four VGA-equipped displays. This unit does not convert or scale signals; it amplifies and splits the source resolution as-is, so both your source and all four displays need to support a common resolution and refresh rate for stable sync. If your displays operate at different native resolutions, use a VGA scaler upstream of the ST124PRO rather than expecting it to resolve mixed-display environments on its own.

This is an analog VGA distribution solution — it does not support HDMI, DisplayPort, or digital signals of any kind. For environments already running digital display infrastructure, review the video distribution amplifier category for HDMI and HDBaseT alternatives. For installations where the ST124PRO will feed displays across a building, pair it with a quality VGA cable rated for the distance — cable quality becomes a real factor at runs approaching the 210 ft maximum. A KVM switch upstream can extend the utility of this setup if multiple sources need to share the same four-display output array.

If you're planning a larger multi-display deployment, review our AV signal distribution guide for advice on cascading amplifiers, cable selection, and resolution matching across mixed display environments.

Frequently Asked Questions

Q: What is the maximum resolution the ST124PRO supports?

A: The ST124PRO supports up to 2048x1536 (QXGA) at 80Hz — well above standard 1080p. All four outputs receive this resolution simultaneously, provided your source and displays support it.

Q: How far can I run cable from the ST124PRO to each display?

A: The specified maximum cable length is 210 feet per output. Beyond this distance, signal quality can degrade — expect ghosting or sync issues, particularly at higher resolutions. Use quality, shielded VGA cable to maximize usable distance.

Q: Does the ST124PRO work with international power?

A: Yes. The built-in power supply accepts 100–240V AC input at 0.3A, making it compatible with power standards in North America, Europe, and most other regions without an external converter.

Q: Can the ST124PRO split HDMI or DisplayPort signals?

A: No. The ST124PRO is a VGA-only device. It handles analog VGA (HD-15) signals exclusively and does not support HDMI, DisplayPort, DVI, or any digital video format.

Q: What is the warranty on the ST124PRO?

A: The ST124PRO carries a 2-year manufacturer warranty.

Q: Is the ST124PRO passive or active?

A: Active. It uses powered signal amplification at 350 MHz to boost and distribute the video signal to all four outputs — unlike passive splitters that simply divide signal strength, which causes visible image degradation at the receiving displays.

Ted Perry

The spec I keep coming back to on the ST124PRO is the 350 MHz active amplification bandwidth. I've seen plenty of cheap passive VGA splitters in control room installs where the client bought them to save $30 and then spent two days troubleshooting why displays three and four looked washed out. The ST124PRO actively regenerates the signal at each output — that 350 MHz headroom means you're not losing edge sharpness even at QXGA (2048x1536), which is exactly the resolution some legacy medical and engineering display setups still run at.

Technical Highlights:

• 350 MHz Active Bandwidth: Enough headroom to maintain signal integrity at maximum resolution across all four outputs simultaneously — passive alternatives typically cap out around 100–150 MHz and show it.
• 210 ft Maximum Reach: Covers most single-story commercial floor plans without a second amplifier. Factor cable quality into the equation at runs over 150 ft — the spec assumes quality shielded cable, not bargain-bin runs.
• Universal 100–240V AC Input: At 5W draw and global voltage acceptance, this unit can be deployed anywhere in a facility without power conditioning concerns. The 0.3A draw is negligible on any commercial circuit.

Deployment Considerations:

• All four displays and the source must negotiate a common resolution and refresh rate — the ST124PRO does not scale or convert. Mixed-resolution display walls require an upstream scaler before the signal hits this unit.
• Operating temperature tops out at 40°C — verify the equipment closet or AV rack environment stays within this band, especially in summer months or in poorly ventilated spaces.

The ST124PRO is the right call for legacy VGA control room buildouts — security monitoring stations, dispatch centers, or training rooms where a single DVR or workstation needs to feed four displays and the entire infrastructure is already running analog VGA. It's not the answer for anyone moving to HDMI or digital distribution, but for the VGA environments that aren't going away anytime soon, it handles the job cleanly.