笔记本电脑(Laptops)很棒，但作为便携式电脑，它们的屏幕空间总是很短。将两台外接显示器连接到计算机可以将其变成真正的生产力强国，但如何将两台显示器连接到笔记本电脑并不总是很清楚。根据您的具体型号，您有许多不同的选择。
将内部显示器(Internal Monitor)与一台外部显示器一起使用(One External Monitor)
如果您只需要两台显示器，除了笔记本电脑内置的显示器外，您还可以使用一台外接显示器。当然，这与将两台显示器连接到您的笔记本电脑不同，但我们知道有些人只想要双显示器设置，但不知道您可以通过这种方式实现它。
如果是你，那么你已经找到了解决方案；只需将外接显示器插入笔记本电脑允许的任何位置，并保持笔记本电脑的屏幕打开。两者应该并肩工作。
使用 Thunderbolt 直通(Use Thunderbolt Passthrough)（如果可用(Available)）
一些现代笔记本电脑具有Thunderbolt 3端口。但是，大多数新笔记本电脑至少有一个 USB-C 端口。两种(Both)技术都使用相同的连接器。如果您需要复习 Thunderbolt(Thunderbolt)，请查看HDG 解释：什么是 Thunderbolt？(HDG Explains: What is Thunderbolt?)了解更多信息。
Thunderbolt 3设备可以“菊花链式”，这对于Thunderbolt 3显示器也是如此。因此，如果您有两台Thunderbolt 3显示器，您可以将第一台插入计算机的Thunderbolt 3端口，将第二台插入链中的第一台显示器。
这是一个优雅的解决方案，但仍然不常见，而且Thunderbolt 3显示器相对稀有且昂贵。如果您已经拥有一个Thunderbolt 3屏幕（您应该检查一下！），那么为这样的设置购买第二个屏幕并不算太离谱，但对于大多数人来说，总支出将太高而无法证明是合理的。
如果您拥有一台最新的Apple M1电脑，遗憾的是(Apple M1)Apple M1 MacBook(Apple M1 MacBooks)有一个限制，它只允许一个外部显示器。Apple已承诺在未来的 macOS 更新中解决此问题，但目前只能通过涉及特定加密狗和显示驱动程序的第三方解决方法来解决。没有原生 macOS 解决方案。
将监视器(Monitor)连接到每种输出类型(Every Output Type)（如果支持）
您的笔记本电脑很有可能具有不止一种显示输出类型。例如，正在写入的计算机同时具有HDMI端口和Mini-DisplayPort输出。第一个连接到专用GPU，第二个连接到集成英特尔 GPU(Intel GPU)。可以将监视器连接到两个输出并同时运行。两台显示器都应与内部显示器一起运行，从而构成三台显示器设置。
这里有一些限制需要牢记。首先(First)，有问题的GPU需要支持所需的显示器数量。现代(Modern)集成CPU(CPUs)通常最多支持三个显示器，因此将覆盖两个外部单元以及内部屏幕。专用GPU(GPUs)通常支持三个或更多。
在您外出购买显示器之前，您需要通过他们的网页、手册或客户支持与您的笔记本电脑制造商确认您的特定笔记本电脑是否支持每个显示输出上的单独显示器。
使用加密狗
超薄笔记本电脑的出现也为我们带来了几乎没有任何端口的一代便携式电脑。最新的Apple MacBook(Apple MacBooks)仅具有Thunderbolt 3端口，基本型号上只有两个端口。如果您想在这些计算机上监控输出，则需要一个加密狗。
如果您想连接多个外部显示器，则需要一个具有多个显示输出的加密狗，或者需要两个加密狗，每个都插入自己的雷雳 3(Thunderbolt 3)或 USB-C 端口。
请记住(Remember)，M1 Apple MacBook(M1 Apple MacBooks)目前对外部显示器有一个显示器限制。对于基于 Intel 的Mac(Macs)和Windows计算机，通常情况并非如此。
使用 USB 显示器
一些显示器提供USB显示器连接，目前市场上也有许多便携式USB显示器。这实际上将您的USB端口转换为额外的显示输出，并提供了一种简单的方法来添加第二个外部显示器，如果您的笔记本电脑只有一个显示器输出。
请记住(Remember)，与其他选项相比，USB显示器可能会出现延迟、较低的刷新率和较低的图像质量。这取决于计算机的性能和可用的USB带宽。它们仍然非常适合Slack、电子邮件或网页等内容。只是不是高质量的视频或视频游戏。
使用多头分离器
市场上的一些设备提供了将单个监视器输出“拆分”为多个的选项。这些设备如何实现这一点可能会有所不同。例如，有些将自己呈现为计算机的单个监视器，并处理跨多个屏幕的图像。使用这些适配器，无法使用操作系统的双显示器功能，因为它认为只有一个屏幕。
因此，全屏应用程序跨越链接到拆分器的所有外部屏幕。如果您使用多个窗口捕捉到虚拟屏幕的每一半，这仍然不是一个糟糕的解决方案。
其他分配器类型比这更智能，但它确实取决于底层显示技术。例如，提供三个端口的DisplayPort集线器将在计算机上注册为多个独立显示器。(DisplayPort)这要归功于称为多流传输(Multi-Stream Transport)( MST ) 的(MST)DisplayPort 1.2 （和更新）功能。使用MST ，您可以像(MST)Thunderbolt 3显示器一样以菊花链方式连接多个DisplayPort显示器。集线器在内部执行此链接，但实际的连接布局与将监视器相互链接相同。
如果您的笔记本电脑具有支持MST的(MST)DisplayPort输出，那么您可以购买其中一个分配器（称为MST集线器）并以比(MST)Thunderbolt 3更低的成本和更广泛的显示器选择来解决您的外部显示问题。
获取专有坞站
虽然使用USB、Thunderbolt和DisplayPort等标准对大多数用户来说已经足够了，但不要忘记存在专有解决方案。许多笔记本电脑都有自定义连接器，可让您添加一个作为本机解决方案工作的扩展坞（有时称为“端口复制器”）。这些对接端口通常使用直接连接到笔记本电脑主板的高速总线的连接，以确保优质的体验和兼容性。
这些扩展坞通常具有大量的显示输出。例如，戴尔 E-Port(Dell E-Port)产品允许兼容的笔记本电脑轻松连接两个外部显示器，提供多个DVI和DisplayPort连接。您是否可以使用此选项将完全取决于您的特定笔记本电脑型号。
您需要两台显示器吗？
虽然将两台外接显示器连接到您的笔记本电脑有很多合法用例，但您应该评估是否需要这样一个复杂的设置来满足您的需求。如果您想要的只是更多的桌面空间，您可能需要考虑使用超宽显示器，它只需要一个显示输出。查看Ultrawide Vs。双显示器(Ultrawide Vs. Dual Monitor)可深入讨论这两个选项以及最适合您的选项。
How to Connect Two Monitors to a Laptop
Laptops are great, but as portable computers, they’re always short on screen real estate. Connecting two external monitors to a computer can turn it into a genuine productivity powerhouse, but it’s not always clear how to connect two monitors to a laptop. Depending on your exact model, you have many different options.
Use the Internal Monitor With One External Monitor
If all you want is two monitors total, you can use a single external monitor in addition to the one that’s built-in to your laptop. Of course, this is not the same as connecting two monitors to your laptop, but we know there will be some who just want a dual-monitor setup and didn’t know you can achieve it in this way.
If that’s you, then you’ve found your solution already; simply plug the external monitor in wherever the laptop allows and keep the laptop’s screen open. Both should work side by side.
Use Thunderbolt Passthrough (If Available)
Some modern laptops have a Thunderbolt 3 port. However, most new laptops have at least a USB-C port. Both technologies use an identical connector. If you need to brush up on Thunderbolt, look at HDG Explains: What is Thunderbolt? for more information.
Thunderbolt 3 devices can be “daisy-chained,” which is also true for Thunderbolt 3 displays. So if you have two Thunderbolt 3 displays, you can plug the first into your computer’s Thunderbolt 3 port and the second into the first monitor in the chain.
This is an elegant solution, but it’s still uncommon, and Thunderbolt 3 monitors are relatively rare and expensive. If you already have one Thunderbolt 3 screen (you should check!), then it’s not too outrageous to buy a second one for a setup like this, but for most people, the total outlay will be too much to justify.
If you own one of the latest Apple M1 computers, there is sadly a limitation on Apple M1 MacBooks, which only allow for a single external display. Apple has promised to address this in a future macOS update, but right now, it’s only possible through third-party workarounds involving specific dongles and display drivers. There is no native macOS solution.
Connect a Monitor to Every Output Type (if Supported)
There’s a good chance that your laptop has more than one display output type. For example, the computer this is being written on has both an HDMI port and a Mini-DisplayPort output. The first is wired to the dedicated GPU, and the second is wired to the integrated Intel GPU. It’s possible to connect a monitor to both outputs and have both run at the same time. Both monitors should run alongside the internal display, adding up to a triple-monitor setup.
There are some limitations here to keep in mind. First, the GPU in question needs to support the number of displays required. Modern integrated CPUs usually support up to three displays, so that would cover two external units as well as the internal screen. Dedicated GPUs usually support three or more.
Before you go out and buy monitors, you need to confirm with your laptop’s manufacturer via their web page, manual, or customer support whether your particular laptop supports separate monitors on each display output.
Use Dongles
The advent of ultra-thin laptops has also brought us a generation of portable computers that have barely any ports at all. The latest Apple MacBooks only have Thunderbolt 3 ports, starting with as few as two ports on the base models. If you want monitor outputs on these computers, you need a dongle.
If you want to connect more than one external display, you either need a dongle with multiple display outputs, or you need two dongles, each plugged into its own Thunderbolt 3 or USB-C port.
Remember that the M1 Apple MacBooks currently have a one-monitor limit for external displays. For Intel-based Macs and Windows computers, this isn’t usually the case.
Use a USB Display
Some monitors offer a USB display connection, and there are also many portable USB displays on the market today. This essentially transforms your USB ports into additional display outputs and provides a simple way to add a second external display if your laptop only has a single monitor output.
Remember that USB displays may exhibit lag, lower refresh rates, and lower picture quality than other options. This depends on the performance of your computer and the available USB bandwidth. They are still excellent for content such as Slack, email, or web pages. Just not high-quality video or video games.
Use a Multihead Splitter
Several devices on the market offer the option to “split” a single monitor output into multiple ones. How these devices achieve this can differ. For example, some present themselves as a single monitor to the computer and handle spanning the image across multiple screens. With these adapters, it’s not possible to use the dual monitor features of your operating system because it thinks there’s only one screen.
As a consequence, full-screen applications are spanned across all external screens linked to the splitter. It’s still not a bad solution if you use multiple windows snapped to each half of the virtual screen.
Other splitter types are more intelligent than this, but it does depend on the underlying display technology. For example, a DisplayPort hub that offers three ports will register as multiple independent displays on the computer. This is possible thanks to a DisplayPort 1.2 (and newer) feature known as Multi-Stream Transport (MST). With MST, you can daisy-chain numerous DisplayPort displays similarly to Thunderbolt 3 monitors. The hub does this chaining internally, but the actual connection layout is the same as chaining the monitors to each other.
If your laptop has a DisplayPort output that supports MST, then you can buy one of these splitters (known as an MST hub) and solve your external display problem for less cost than Thunderbolt 3 and with a broader choice of monitors.
Get a Proprietary Docking Station
While using standards such as USB, Thunderbolt and DisplayPort will be good enough for most users, don’t forget that proprietary solutions exist. Many laptops have custom connectors that let you add a docking station (sometimes referred to as a “port replicator”) that works as a native solution. These docking ports often make use of a connection that runs directly to the high-speed buses of the laptop’s motherboard, ensuring a premium experience and compatibility.
These docking stations usually have a multitude of display outputs. For example, the Dell E-Port products allow compatible laptops to easily connect two external monitors, offering multiple DVI and DisplayPort connections. Whether this option is available to you will depend entirely on your specific laptop model.
Do You Need Two Monitors?
While there are many legitimate use cases for connecting two external monitors to your laptop, you should evaluate whether you need such an elaborate setup for your needs. If all you want is more desktop space, you may want to consider an ultrawide monitor instead, which only needs a single display output. Check out Ultrawide Vs. Dual Monitor for an in-depth discussion of both options and which is best for you.
