The $399 Razer Core X Chroma is the ultimate laptop accessory: it’s an external graphics card (eGPU) enclosure that, with a single Thunderbolt 3 cable, can significantly boost graphical performance of a slim laptop and provide an assortment of extra USB ports and connections.

Like other eGPU enclosures, the Core X Chroma arrives empty yet full of promise. In addition to the enclosure, you’ll need a computer with a Thunderbolt 3 port and an AMD (the only option for macOS users) or Nvidia desktop graphics card. These range in price from around $200 to $1,200, depending on how much power you’re looking for.

This isn’t Razer’s cheapest or most expensive eGPU. The Core X Chroma splits the price difference between the $299 Core X and the $449 Core V2, and its feature set borrows their best features, then slightly refines them.

More ports are always a good thing

The Core X Chroma comes with a 700W power supply, which makes it 50W more powerful than what was included with older Razer Core enclosures. It caps the power usage of the GPU installed to 500W, though none of the supported GPUs come close to taking full advantage of that allowance. Still, the extra wattage is appreciated since it has four USB 3.1 ports on its back that can be used for peripherals like a mouse and keyboard.

Our review of Razer Core X Chroma Verge Score 7.5 out of 10 Good Stuff More power and ports for USB accessories

Chroma lighting effect is understated

The novelty of boosting a laptop’s power with a single cable doesn’t get old Bad Stuff The $100 premium is barely justified

Thunderbolt 3 inherently bottlenecks GPUs Buy for $399.99 from Razer Buy for $399.99 from Amazon

More ports are always a good thing, especially since most Thunderbolt 3-ready laptops are lacking in them. It also has an Ethernet jack to increase download speeds and minimize latency versus gaming over Wi-Fi. All of these extra ports and connections mean you can use the Core X Chroma like a dock, with your mouse, keyboard, external display, and wired network connection plugged into it, instead of having to make all of those connections every time you sit down at your desk.

Razer’s multicolor LEDs also make an appearance in the Core X Chroma. You’ll get the most out of the effect if you already own other Razer products that support the system. Its Synapse software (which isn’t available on macOS) can sync up the lighting effects across the devices for a coordinated light show, or you can tweak them individually to look different. It’s superfluous, though, I’ll admit, seeing the graphics card dimly lit through the side panel of the Core X Chroma looks cool.

Our review unit was stocked with an RTX 2070, which we swapped out for a more powerful RTX 2080 Ti. Opening the enclosure is a tool-free affair and simple to do: just move a lever and give it a pull. Then, it’s much like operating on a desktop motherboard (without every other component getting in the way). Align the GPU with the PCIe slot, push it in until a latch clicks, and plug in your GPU’s required number of 6- or 8-pin PCIe power connectors.

I tested the Razer Core X Chroma with the lowest-spec Razer Blade Stealth laptop, which relies on integrated graphics. By its looks alone, the Blade Stealth is a gaming laptop, though it can’t run the latest AAA titles without making serious compromises to the display resolution and graphical quality. So, it’s the perfect test subject.

If you’re using a MacBook, you’ll need to use an external monitor to see the benefits

You can get away with just using the Razer Blade’s display to play games, though the enclosure allows the inserted graphics card to output to multiple monitors. Things work differently for macOS laptops. According to Razer’s documentation, the Razer Core X Chroma won’t boost gaming performance on a MacBook laptop’s display. You’ll need to hook up an external monitor (or buy one, if you don’t have a spare handy) to see any benefits from using the eGPU enclosure. But if you’re serious about gaming, you’re probably not using a Mac anyway.

Coming back to the Blade Stealth, games like Prey and Rage 2 run at smooth, consistent 60 frames per second at maximum settings, though that’s not the limit of what this setup is capable of. The Blade Stealth comes with a 1080p display with a 60Hz refresh rate by default, so in the interest of seeing how the Core X Chroma performs on a screen with a faster refresh rate, I also tried it with the Razer Blade 15 with a 144Hz display.

Grid View Photo by Amelia Holowaty Krales / The Verge

Photo by Amelia Holowaty Krales / The Verge

Photo by Amelia Holowaty Krales / The Verge

The Razer Blade 15 has a dedicated graphics card, the RTX 2060, and before I could get the eGPU enclosure working, I had to download Razer’s GPU switcher app to force Windows 10 to recognize the RTX 2080 Ti as the primary GPU. As expected, those same games, as well as others like Apex Legends and Shadow of the Tomb Raider, performed well above 60 frames per second. These games went above 100 frames per second at times, though, none of them came close to taking full advantage of its 144Hz refresh rate. The RTX 2080 Ti is currently the fastest gaming GPU, so the likely culprit for these lower-than-expected numbers is Thunderbolt 3.

It’s the best low-maintenance fix for a high-maintenance problem

Capable as it is at quickly moving data, Thunderbolt 3 puts a noticeable bottleneck on a GPU’s bandwidth. It supports four lanes over PCIe, which is significantly fewer than the 16 lanes of PCIe supported on most desktop motherboards. (Some laptops have even less bandwidth on their Thunderbolt 3 ports, so you’ll have to check with your manufacturer’s specs to see exactly what your laptop is capable of.) When you’re gaming on a laptop’s display, the single cable is pulling double duty: the computer has to send data to the GPU for processing, then receive the processed data back to be displayed. Playing intensive games is a huge workload, and, ultimately, even the most powerful graphics cards out there will struggle to display truly impressive frame rates. Despite this, I didn’t notice any choppiness in gameplay.

The perfect solution for bringing desktop-grade gaming performance to laptops may never exist. It’s a moving target that is always improving and, so long as eGPU enclosures are running up against the limitations of Thunderbolt 3, it might be a while until something better comes along.

Still, the execution on Razer’s end for the Core X Chroma is as good as it currently gets, and the novelty of vastly improving the performance of your light, portable laptop with a single cord doesn’t fade. It’s the best low-maintenance fix for a high-maintenance problem.