How to check performance on an eGPU dock

Your laptop is connected to an external GPU, but it is not obvious whether the eGPU is doing useful work. A game may still feel slow, or a benchmark score may look much like it did before you connected the dock.

Start with a repeatable graphics test, then check how the browser is using the GPU. The Graphics Test measures shading power and fill rate at 1080p and gives a score out of 100. It can help compare the same computer in different setups, but it is not a game benchmark.

Test the eGPU setup

Connect the eGPU using the port and cable supported by the enclosure, then turn on the enclosure. A USB-C-shaped port does not always support the connection an eGPU needs. If you want to test gaming on an external monitor, connect that monitor directly to the eGPU.
Close games, video editors, and other demanding apps. Keep the laptop plugged into power, and leave the same browser and power settings in place for each run.
Open the Graphics Test in the browser you want to check. Run it with the eGPU connected and note the score. Also note whether the browser is on the laptop screen or an external monitor.
Repeat the test two more times without changing the setup. Write down all three scores and look at the typical result, not just the highest one.
If you want a comparison, disconnect the eGPU using the enclosure or operating system instructions, then test again with the laptop's built-in graphics. Keep the browser and other conditions as similar as you can. If you change screens or display connections, treat the comparison as an estimate rather than a perfectly controlled test.

For a useful comparison, keep the laptop's power mode, browser, browser window, and display scale consistent. Windows 11 display scale is under Settings › System › Display. On macOS, check System Settings › Displays. A change in scale or display setup can affect browser rendering and complicate comparisons. See how display scale can change graphics results.

What the result means

The eGPU score is clearly higher

The browser's graphics workload ran faster with the eGPU connected. That is evidence the eGPU setup helps with this kind of browser rendering. It does not guarantee the same improvement in a game or other app, because each program can choose a different GPU and use it differently.

The scores are close

The eGPU may not be handling this browser test, or the test may not be demanding enough to show a difference. The browser could be using the laptop's built-in GPU. The eGPU connection, driver, or display route can also limit the benefit. Check the settings below before assuming the dock is faulty.

The score changes a lot between runs

Other work may be using the GPU, or the laptop may be changing its power or cooling behavior. Let the computer cool, close demanding apps, and repeat the test under the same conditions. For additional context, read what a browser graphics score can and cannot tell you about VRAM.

The score is low, but the eGPU appears connected

A connection alone does not prove the browser is using the external card. The browser may be using integrated graphics, or the eGPU may have limited performance because of the connection or the way frames reach the screen. A browser test cannot identify every cause.

How to improve the test

Check which GPU the browser can use. On Windows 11, open Settings › System › Display › Graphics, select your browser, choose Options, and select the eGPU as the high-performance option if Windows lists it. Close and reopen the browser after changing this setting. On an Intel Mac that supports eGPU, check the browser app's Finder Get Info window for Prefer External GPU, if that option is available. Apple silicon Macs do not support eGPUs.
Try an external monitor connected to the eGPU. When an eGPU renders a frame for the laptop's built-in display, the frame has to travel back to the laptop over the connection. A monitor connected directly to the eGPU can avoid that return path and may improve performance. Compare that setup separately, since the display route has changed.
Check the cable and port. Connect the enclosure directly to a supported Thunderbolt or USB4 port, without a hub or dock in between. Use the enclosure maker's recommended cable and confirm the enclosure has power.
Restart the browser after connecting the eGPU. Some browsers choose a graphics device when they start. Quit the browser completely, reconnect the eGPU, and open the browser again before testing.
Update the graphics driver and browser. On Windows, install a compatible driver for the eGPU from its GPU manufacturer or enclosure instructions. On a Mac, install available macOS updates for your supported Intel Mac and eGPU. Then restart and test again.
Reduce background GPU work. Close other browser windows that show video or animated content, as well as games and graphics-heavy apps. Wait a minute between runs if the laptop or enclosure is warm.

When the dock or GPU may be faulty

A small score gain does not by itself mean the eGPU is broken. Browser rendering may not use the card in the same way as your main app, and an eGPU connection can be slower than a desktop GPU connection. Test a demanding app that supports the eGPU too, and check whether the card appears normally in the operating system or the manufacturer's utility.

If the eGPU repeatedly disconnects, disappears from the system, or produces errors across more than one supported app, try the enclosure's recommended cable and another compatible port. Follow the enclosure maker's safe removal instructions before unplugging it. If the problem continues, contact the enclosure or GPU maker about warranty service.

What this browser test cannot show

The Graphics Test is a consistent browser workload, not a full check of the eGPU's specifications. Its score does not identify the GPU's exact model, prove how much VRAM is available, or predict frame rates in a specific game. It also cannot confirm that every app on your computer will use the eGPU. Use it to compare repeatable runs, then check the GPU selection and performance inside the app that matters to you.