[tl;dr: Yes you can drive 4 or even 6 external monitors each with distinct content and from almost any PC laptop. But there is a catch…]
Start with a regular Dock for the first 2 monitors
Many laptop users only use the built-in laptop LCD, but some need more screen real-estate. Almost all laptops can drive a single external monitor by plugging the monitor in directly. Two monitors can be plugged into most laptop docking stations with distinct content on each screen via DisplayPort or HDMI connectors. There are 4 main docking station styles that support multiple monitors:
- PC vendor’s branded dock (Microsoft Surface Dock 2, HP workstation dock, Dell workstation dock, Lenovo workstation dock, etc.)
- USB-C Dock with DisplayPort alternate mode and two distinct video outputs (check the laptop manufacturer’s website for compatibility to ensure its USB-C port can output video)
- Thunderbolt 3 / Thunderbolt 4 Docks with two or more distinct video outputs. It’s the same physical connector as USB-C but with a different data protocol. Note that some Thunderbolt 4 docks can support 3 or 4 monitors directly.
- DisplayLink technology dock/hub with USB-C or USB-A connector (not recommended for connecting the first 1-2 monitors due to lag/latency issues)
Options 1-3 are a great start!
Adding more monitors
Brief history lesson
Most laptops are limited to driving a maximum of 2 or 3 screens including the built-in screen. Back in the Windows Vista timeframe, there were a few vendors offering inexpensive VGA-over-USB-2.0 solutions where a little dongle plugged into a standard USB A provided an extra VGA or DVI monitor output beyond whatever limit your PC had. Suddenly, cheap quad monitor arrays were possible on entry-level PCs. Performance on these early USB-video dongles was poor with disruptive lag/latency and frequent glitches. This was due to a reliance on software which essentially hacked into the Intel, AMD, or NVIDIA GPU device drivers with a method that was not well-vetted by Microsoft or the GPU vendors. When Windows update service packs were applied, the method would break leaving the screen blank and you’d have to wait weeks for fixes.
With Windows 10, however, Microsoft introduced an indirect display driver model which prescribes reliable and performant methods to attach displays to USB. Monitors attached this way still do not perform as well as monitors connected directly to a GPU. They usually have an added lag/latency of 3-6 frames (50-100ms at 60Hz refresh rate) which makes for a poor gaming experience – but OK for most office and creative applications. Below, a handful of devices using these newer software interfaces and chipsets are listed. These devices can be used to add 1-2 additional monitors at 4K60 resolution to your laptop, existing docking-station, or desktop PC beyond the typical 3-screen limitation of most PCs.
Because of the added latency with USB video extenders and Docks designed around DisplayLink technology, it is best to start with a regular docking station first. For example, on a Microsoft Surface, get the Surface Dock for the first 2 monitors, then add a third and fourth with a USB 3.x video extender. Or on a Lenovo, start with a USB-C or Thunderbolt 3 dock which takes advantage of DisplayPort alternate mode and add a third and fourth monitor with a USB video extender.
For folks that need to use multiple 4K60 monitors but have an older laptop that can only run 4K30, just use a video extender to provide the necessary 4K60 outputs.
What should you buy?
Less expensive USB video extenders exist from a variety of manufacturers in the $20-$50 price range with varying capabilities, performance, and vendor support. But I’ve had the best luck with Plugable, StarTech, and Cable Matters devices based on the latest DisplayLink chipset technology and use these in customer builds. I have less experience with Silicon Motion based products, but my understanding is that DisplayLink has superior software support.
USB Video extenders supporting 4K resolution
| Device | PC port | Monitor #1 port | Monitor #2 port | Max res/ refresh | Other ports | Chipset Vendor | Price ($USD) |
| Cable Matters 202048-BLK | USB 3.x | HDMI | N/A | 4K30 or 1080p60 | N/A | DisplayLink | ~$70 |
| Cable Matters 202049-BLK | USB 3.x | DisplayPort | N/A | 4K30 or 1080p60 | N/A | DisplayLink | ~$75 |
| Plugable USB-C-6950-DP | USB-C | DisplayPort | DisplayPort | 2x 4K60 | Ethernet | DisplayLink | ~$85-100 |
| Plugable USBC-6950U | USB-C or USB 3.x | HDMI or DisplayPort | HDMI or DisplayPort | 2x 4K60 | N/A | DisplayLink | ~$100 |
| StarTech USBA2DPGB | USB 3.x | DisplayPort | DisplayPort | 2x 4K60 | Ethernet | DisplayLink | ~$80-100 |
| Plugable USB3-6950-HDMI | USB 3.x | HDMI | HDMI | 2x 4K60 | Ethernet | DisplayLink | ~$85-100 |
| Plugable UGA-4KDP | USB 3.x | DisplayPort | N/A | 4K60 | N/A | DisplayLink | ~$60-75 |
| StarTech USB32DP4K | USB 3.x | DisplayPort | N/A | 4K60 | N/A | DisplayLink | ~$60-75 |
| Plugable UGA-4KHDMI | USB 3.x | HDMI | N/A | 4K60 | N/A | DisplayLink | ~$60-75 |
| StarTech USB32HD4K | USB 3.x | HDMI | N/A | 4K30 or 1080p60 | N/A | DisplayLink | ~$50-60 |
| Plugable UGA-HDMI-2S | USB-C or USB 3.x | HDMI | HDMI | 2x 4K30 or 1080p | N/A | Silicon Motion | ~$70 |
| Plugable UGA-DP-S | USB-C or USB 3.x | DisplayPort | N/A | 4K30 or 1080p60 | N/A | Silicon Motion | ~$65 |
| Startech USB32HDVGA | USB 3.x | HDMI | VGA (mirrored) | 4K30 or 1080p60 | N/A | Silicon Motion | ~$100 |
More adapters:
- https://www.startech.com/en-us/audio-video-products/display-and-video-adapters/usb-video-adapters
- https://plugable.com/collections/usb-graphics-adapters
USB Video extenders supporting 2K resolution
| Device | PC Port | Monitor #1 port | Monitor #2 port | Max res/ refresh | Other ports | Chipset Vendor | Price ($USD) |
| Cable Matters 103046-BLK | USB 3.x | HDMI | N/A | 2560x1440p50 or 1920x1080p60 | N/A | DisplayLink | ~$50-60 |
| Plugable UGA-2KHDMI | USB 3.x | HDMI | N/A | 2560x1440p50 or 1920x1080p60 | N/A | DisplayLink | ~$50-55 |
| StarTech USB32HDPRO | USB 3.x | HDMI | N/A | 2560x1440p50 or 1920x1200p60 | N/A | DisplayLink | ~$60-65 |
More info
USB-C DisplayPort Alternate mode and MST hubs
Many modern laptops include built-in USB-C, Thunderbolt 3, or DisplayPort receptacles. When monitors are connected to these ports, they use the laptop’s GPU directly so there is no added lag/latency. But not all USB-C ports support this direct connection to the GPU. In order to support it, the USB-C port must enable “DisplayPort Alternate mode”. Unless your laptop manufacturer indicates monitor connectivity offered by the USB-C port, it may only be suitable for data and/or charging. Also, the specific monitor capabilities such as resolution and refresh rate offered by the port can differ between laptop models. For example, here is an article describing the differing monitor support for Microsoft Surface device USB-C ports.
Even if your laptop only has 1 monitor output port via USB-C or DisplayPort, you may still be able to connect multiple monitors directly to the GPU with MST technology. MST stands for “multi-stream-transport” and is a method to split a DisplayPort signal into multiple monitors by sharing the bandwidth between them. This technology is specific to DisplayPort (and USB-C with DisplayPort alt mode) and can either be implemented via a discrete MST hub, a docking station with a built-in MST chipset, or a daisy-chain output port built into a monitor. Windows and Linux support MST well, but MacOS does not. Most laptops limit the number of distinct screen outputs to 3 (including the built-in laptop screen if it is switched on). So if you try to connect additional monitors beyond this limit, they will go blank or display the same content as one of the other screens. (DisplayLink and similar video extender technologies have no such 3-screen limitation.) Many OEM docking stations have a built-in MST hub to provide two monitor outputs. Using an additional MST hub in tandem (cascade configuration) with these docking stations to gain a third output is not recommended due to compatibility issues. The following table compares MST hubs vs USB video extender technology:
| Performance characteristic | MST Hub | USB Video extender adapter/dongle |
| Added Latency | negligible | 50-100ms |
| Maximum # of screens | 3 | 8 (up to 16 is technically possible but impractical for most PCs) |
| Maximum # of 4K60 screens | limited to PC specification – typically 1 or 2 | 4 (up to 8 is technically possible but impractical for most PCs) |
| Maximum screen resolution | 1080p – 8K30 depending on PC | 4K60 (5K60 when combining two outputs/cables to a single compatible monitor) |
| Maximum refresh rate | 60Hz – 144Hz depending on PC (60Hz is typical) | 60Hz |
| Requires external power | some | no (Docking-station devices may require external power) |
| OK for office apps? | yes | yes |
| OK for intensive video and 3D graphics apps? | yes | most (latency may affect smoothness of animations) |
| OK for casual games? | yes | most (latency may affect gameplay) |
| OK for intense 3D games? | yes | no (high CPU usage and high latency likely to ruin the gaming experience) |
| OK for 4K fullscreen video? | yes | yes (but with moderate CPU usage) |
| Uses CPU cycles? | no | yes (negligible CPU load for most applications on modern PCs in Windows 10) |
| Has additional USB, audio, or Ethernet ports? | no (additional ports available on docking-station devices) | additional ports available on some models |
| Uses which port on the laptop? | DisplayPort, miniDP, or USB-C depending on model | USB-C or USB 3.x A-type depending on model |
| Cascade multiple hubs | Not recommended (Connecting an MST hub to a device that already has an MST chipset such as OEM docking stations often won’t work and one screen will be blank.) | Not recommended (Downstream USB ports on DisplayLink-based Docking-station devices can be used for connecting an additional Video extender, but may yield poor performance due to bandwidth constraints) |
| Monitor Daisy-chain support | Some – Daisy chaining compatible monitors from a single port may work on some models | no |
| Cost ($USD) | ~$50-130 for name brand devices | ~$50-100 for name brand devices |
A variety of MST hub styles are available:
- USB-C DisplayPort alt mode MST hubs
- DisplayPort MST hubs
- MiniDP (Mini DisplayPort) MST hubs
- MST hubs with built-in HDMI outputs
Chipset technology vendors for USB-based video extenders
- DisplayLink/Synaptics
- Fresco Logic/ParadeTech
- limited Win7/8/10 support driver software last updated 2020
- MCT “Ttrigger” series
- Silicon Motion
- SMSC/Microchip
- end-of-life product – Windows 7/8 software last updated in 2014
Note: products based on different technology vendors conflict and cannot be used together on the same system. You must completely uninstall any software from one vendor in order to switch to a product from another vendor. For example, DisplayLink provides explicit instructions on removing other vendor’s software.
MacOS support
These devices are not well-supported on the latest versions of MacOS. Check with the underlying technology vendor.
DisplayLink vs DisplayPort
DisplayLink is a brand name and a division of Synaptics Inc. while DisplayPort is the name of an open video electronics standard for monitor connectivity that describes a physical port and electrical signaling standard and makes recommendations on software/hardware implementations.
The name DisplayLink was chosen during the time period when DisplayPort was already in development but not yet widespread and has caused confusion among consumers and IT professionals. Remember that when connecting a monitor to any computer – DisplayPort is directly connected to a GPU and is always better than connecting via DisplayLink. DisplayLink inserts an additional layer of software and hardware between the GPU and the monitor which *always* compromises performance to some degree. DisplayLink and similar technologies should only be used when all direct connections to the GPU have been exhausted or when those connections offer limited resolution/refresh rate capabilities that are unsuitable for the intended monitors.
Alternatives to multiple monitors
Instead of getting multiple small monitors, consider getting a single 43″-class 4K Home Theatre screen with HDMI 2.0. These screens are compatible with PCs and for their size are considerably less expensive than the combined cost of multiple PC monitors. For multi-tasking, there are a multitude of 3rd-party apps to make it simple to arrange your applications such as Microsoft Powertoys. Below, the benefits and drawbacks of PC vs Home Theatre screens for Desktop computing are compared:
| Performance characteristic | Triple 1080p or 1440p PC monitors | 4K 40-43″ class Home Theatre monitor |
| Added Latency/ Response time | none | some on cheaper models; look for models with a “PC mode” in the on-screen menu system and check rtings.com for latency stats |
| Connector styles | DisplayPort, HDMI, DVI, and/or USB-C | HDMI |
| Refresh rates | 60Hz – 144Hz depending on resolution; adaptive-sync/G-sync available for gaming; 165Hz-360Hz available for specialized gaming-oriented monitors. | 60Hz (120-240Hz via interpolation/motion blur schemes which is typically only helpful for movies) |
| Aspect ratios available | 16:9, 16:10, 21:9, 32:9, etc. | 16:9 |
| VESA arm mountable | Most with 100x100mm | Most with 200x200mm or 100x200mm |
| Bezels | Thin bezels available; bezels between screens can help some users arrange apps but can otherwise be disruptive | Thin bezels available; software tools like Microsoft PowerToys can help arrange apps |
| Designed Viewing distance | 2-3 feet (50-100cm) | 6-10 feet (2-3m) |
| Pixel density | ~82-144 ppi depending on resolution & size | ~100 ppi (lower for larger screens) |
| Color reproduction | Various modes available for print, photo, film, video, gaming, etc. | Optimized for movies, TV, and console gaming |
| High Dynamic Range | Available, but not common | Available |
| Brightness | 300+ nits | 600+ nits |
| OTA HDTV tuner built-in | no | yes |
| Cost ($USD) | $300+ | $250+ |
Dan S. Charlton 
Hi. Thank you for the time to write this. So the idea is to use 2 separate technologies for a Quad Monitor setup? One with DisplayLink? the other without?
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Thanks very much for the thorough and helpful blog. My workplace switched from desktops to laptops and I was very sad to learn that my GPU would only support a total of three monitors (when I currently have four). Your article was very helpful and I ended up purchasing a StarTech extender and I am now happily back to four (well actually 5 now including the laptop!) monitors! Thanks very much! The folks at StarTech should support you as I am sure you send a lot of business their way (for good reason). Thanks again!
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Wow! Thank you so much for writing about this! We have a 4 monitor setup running the Targus QUAD docking station. It has always felt a bit buggy. I’m looking for better performing setup and have three questions.
1) Above you talk about starting with a regular dock and then using an extender. Does the extender plug into the laptop too or into the regular dock?
2) With all the different ports I get confused about which I should be using. Should I use all 4 as DP for best results or 2 DP and 2 HDMI or ???
3) Regarding monitors. We’ve been using monitors that are HDMI. does it work ok to use cable that connects DP (on the port) to HDMI on the monitor, or do we need to be using monitors that have a native DP connection so I can go DP to DP?
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Typically, you’d plug the extended into one of the USB ports on the Dock
DP is superior to HDMI so always use that if you have the opportunity. Otherwise, the video extenders with HDMI outputs or DP->HDMI 2.x adapters are OK.
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Thank you!
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Did you ever find an answer to your questions?
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We’ve bought some different docks and continued onward. don’t love the performance, but we’ve not tried a different route such as described above.
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