Cooler Master MasterCase EG200 in hands-on test: Does an external GPU via Thunderbolt case make sense?

The rather high weight is immediately noticed when unpacking the case, which is probably due to the sturdy metal design and the 550 W power supply. My kitchen scale, which usually weighs every laptop without any problems, was overtaxed ("err") with the MasterCase including the built-in GPU. A less accurate luggage scale came to 6.25 kg (~13.8 pounds, with RTX 3070)! Without the GPU, the case still weighs 5.2 kg (~11.5 lb), so it is really more suitable for stationary use.

As a graphics card, we use an MSI Ventus 3x GeForce RTX 3070 with triple fan design, so it has quite a considerable length. Of course, it is not included in the scope of delivery.

Inside is an accessories pack with a power, a MicroB and a USB-C cable as well as an adapter (USB-A to -C), cable ties and two screws for the GPU bezel.Free cables are secured along the casing with simple cable ties.

After removing two metal rails, the case is exposed for inserting the GPU. Our MSI model is over 30 cm (~11.8 inches) long and still doesn't quite exhaust the case, but almost, maximum GPUs up to a length of 330 mm  (~13 in) fit inside. The GPU with its 2 slot bezels is carefully pressed into the PCI slot, snapped into place and the bezels are secured with screws. Then the PCIe connectors have to be connected. Although there are two 6+2 connectors on one cable, the manufacturer recommends using the second connector cable for cards with a TDP over 250 W, so that the consumption is divided among several rails on the power supply. Connecting the additional cable to the PSU is quite tricky, though, since the connectors for it are located underneath the PSU, but there is only minimal distance to the case bottom and thus little room for handling.

After inserting and connecting, the rails and the top and side parts are screwed back on. Here is a small warning: You should only tighten the screws with minimal force, preferably only hand-tight. It happened to me that a screw was screwed in too far. These have only a very short screw thread, followed by a metal pin without thread. The screw disappeared in the housing to the point that its thread was through and it sat in the hole only with the threadless metal pin. Stupidly, it could not be screwed back out. This happened because the metal spacer holes that promised stability quickly bent. So please tighten the screws only a little more than hand-tight.

To keep the performance loss to a minimum, the GPU in the MasterCase is best connected directly to an external monitor. This was not a problem, but we subsequently had problems with the reactivated internal GPU not wanting to control our external monitor, which was the case in both test laptops. New Nvidia drivers or a temporary uninstallation of the iGPU in the device manager helped here.

The case is connected to the laptop via the included Thunderbolt cable. However, this is much too short! With a cable length of 50 cm (~20 in), the case has to be placed directly next to the laptop and can't be banished to the bottom of the desk, for example. You might have to buy a longer cable yourself, but the short cable should suffice for the first tests.

At first start, Windows sets up the Thunderbolt device again, and for security the internal dGPU can also be disabled, if one is available. The setup went smoothly and only a short time later the screen content was displayed correctly.

We compared two designated gaming laptops with the MasterCase, which is perhaps not entirely fair. On the positive side, we were able to play reasonably up-to-date games in Full HD with maximum details on both laptops with the eGPU. Office machines with a Thunderbolt port should thus benefit greatly from the MasterCase, depending on the GPU used. Owners of laptops with outdated GPUs can also retrain their non-gaming systems to become gamers with the MasterCase.

Of course, the performance of the RTX 3070 in the MasterCase EG200 cannot be compared to the performance in a desktop PC via Thunderbolt. Overall, comparisons are extremely difficult; each game and application obviously reacts differently to the eGPU connected via Thunderbolt. In some cases, the RTX 3070 used in this way cannot even beat a GTX 1060 Mobile, in other cases it even reaches the performance of a desktop RTX 3070 (X-Plane). However, office laptops or notebooks with older GPUs below the GTX 1000 series should clearly benefit from the MasterCase, depending on the installed GPU.

Last but not least, the undertaking is not quite inexpensive. You pay about 350 Euros (~$420) for the MasterCase EG200, plus the price for a decent GPU. In our case, the RTX 3070 used costs 529 Euros (~$635, RRP). However, you do not get the constant performance of an RTX 3070 for around 880 Euros (~$1057) depending on the application, but a very fluctuating performance.

The MasterCase EG200 is practical for making 3D-weak laptops gaming-capable. However, the project is very expensive in view of the large performance fluctuations, and the price-performance ratio is rather insufficient. The MasterCase tries to mitigate this with extra features like hot-swap HDD/SSD and more.