Last year, we briefly checked out external GPUs while we reviewed the Aorus GTX 1070 Gaming Box connected to a Kaby Lake-powered ultraportable. Now that Intel’s 8th gen CPUs are widely to be had in a number ultrabooks, with significant performance gains in hand, it’s the ideal time to revisit eGPUs and determine whether the hard CPU bottleneck still exists in most video games.

As a short recap, final time we tested the GTX 1070 Gaming Box attached to a Lenovo ThinkPad X1 Carbon over Thunderbolt three. The Gaming Box does include a completely-fledged computer GTX 1070 GPU, however the vulnerable Core i5-7200U with just cores and 4 threads offered a bottleneck in basically all games we examined. The eGPU did transform the ThinkPad from a graceful ultraportable into a true gaming system with decent enough overall performance, but the complete energy of the GeForce GTX 1070 wasn’t unleashed by means of any stretch.

In reality, the GTX 1070 eGPU + ultraportable pc aggregate changed into usually 30 to 50 percentage slower than a conventional GTX 1070 gaming laptop, and might be as much as 65% slower in CPU-limited titles. Stuttering became also a noticeable problem in a few (but now not all) games I tested with, which contributed to vulnerable 1% low framerates.

In most video games, when comparing those vital 1% low consequences, the GTX 1070 eGPU became slower than a GTX 1060 gaming laptop, and frequently through a good sized margin. Again, most of this got here down to the CPU bottleneck, and additionally the bandwidth obstacles of Thunderbolt 3. After all, Thunderbolt three handiest provides as much as PCIe 3.0 x4 to the GPU minus a few protocol overhead.

So on this eGPU revisit we’re continuing the quest to discover the closing portable gaming setup, and upping the ante in two regards:

First, Gigabyte kindly swapped out our GTX 1070 Gaming Box for their more moderen and quicker Aorus GTX 1080 Gaming Box. These eGPUs include a portraits card set up, and are supposed to retail for round $seven-hundred, although with the present day GPU scarcity and price hikes, these boxes are rare. Hopefully, as the portraits card market returns to everyday, these containers may also turn out to be more available.

The GTX 1080 Gaming Box is quite similar to its predecessor, so we’re not going to speak a whole lot approximately the design and build because it’s basically similar to earlier than. Key matters to word are the identical compact length, and that it’s still plug-and-play over Thunderbolt 3. It will even price your laptop in the technique, supplied it supports USB Power Delivery.

Even though the new GTX 1080 Gaming Box makes use of a beefier GPU, and as a end result makes use of a bigger heatsink and fan, the field itself isn't any louder than the unique, and doesn’t run distinctly hotter either. It’s marvelous that Gigabyte controlled to fit a complete GTX 1080 and a electricity supply interior a tool this small; it’s a lot smaller than other eGPU enclosures in the marketplace including the Razer Core.

Second, and most importantly, we’re testing with new ultraportables that use eightth gen Kaby Lake Refresh CPUs. With 4 cores, eight threads, and more than a 50% performance leap over the previous generation, there’s desire that the brand new CPUs in these laptops will help address the CPU bottleneck we at first experienced.

If you want a more targeted review on the overall performance of the eightth gen U-series CPUs, take a look at out our complete evaluation.

The laptops we used for eGPU checking out are the HP Spectre x360 and the Razer Blade Stealth, both of which use the Core i7-8550U, the maximum usually used ‘excessive-quit’ 8th gen pc CPU.

Both have 4 lanes of PCIe over Thunderbolt 3 -- in contrast to different laptops that have just two lanes -- and each have 16GB of RAM. The Spectre x360 is configured to use the default 15W CPU TDP and is a bit thermally constrained, as we explored in our review of the pc. The Razer Blade Stealth is also a 15W pc however manages to preserve better clock speeds, in the variety of 300 to 400 MHz better at regular kingdom.

It’s essential to point out we tested everything the use of an outside 1080p display hooked up to the GPU display outputs on the GTX 1080. Performance is fantastically reduced when sending the show signal again to the pc’s display, and we desired to keep away from this sort of slowdowns. We recommend all of us planning to apply an external GPU to apply an outside display for gaming functions, otherwise stuttering and performance losses grow to be a factor.