Anirudh RegidiJuly 9, 2021 12:40:17 PM IST
External graphics processors have been around for some time, but their popularity has risen 3-4 years ago, but they have mostly ceased.
A traditional eGPU includes a full-size desktop-class GPU housed in a case and connected to a laptop or computer (in some cases) via a Thunderbolt 3 interface. On paper, this is great, but the execution penalty is severe.
The GPU normally connects to your computer through an interface called PCIe, and requires 16 PCIe bands for performance. Depending on the graphics processor you use, there are also 8 lanes, and the performance of mid-range and high-end graphics processors is limited to a few percentage points.
The Thunderbolt interface used by EGPUs, on the other hand, offers only 4x PCIe bands at best, and half that if the eGPU drives the laptop’s internal display.
While you could never get desktop-class performance from these cases, they looked like a great way to improve the performance of your current laptop.
Personally, I was never a fan of this design. Sure, you can convert an Ultrabook to a gaming laptop, but eGPUs are expensive, not portable, and cumbersome to install. If I have to dedicate permanent space to a thick eGPU box and external monitor, pay a premium for the case and desktop GPU and am willing to compromise on performance, why not just buy a slightly larger, more powerful game for a laptop? Or better yet, why not build a computer?
Asus has tried to resolve these issues with ROG XG Mobile, and I think Asus has succeeded since fashion.
What is XG Mobile?
Unlike most eGPU options, the XG Mobile is a standalone combination of an eGPU and a USB hub that can accommodate either an RTX 3070 or RTX 3080 GPU. The catch is that these are mobile versions of the 3070 and 3080 and are not user replaceable. The 3080 can operate at up to 150 W, while the 3070 can operate between 125 and 140 W depending on the heating surface.
With a mobile GPU, Asus can cut enough fat to produce an eGPU that is about as thick as a laptop power brick and maybe three times wider. It’s still big, but now it’s small enough (and light enough) to throw in a bag.
Another change is the interface, which uses its own Asus connector – can only be found ROG Flow X13 laptop so far – delivers 8x PCIe 3.0 bandwidth to the eGPU, removing the biggest bottleneck.
In addition, you get a set of I / O in the eGPU box, including: HDMI 2.0b, DP1.4 with G-Sync, RJ45 LAN, 4x USB 3.2 Gen 1 Type-A and an SD card reader rated UHS-II speeds.
The dock comes with its own 280 W power brick, which is enough for the RTX 3080 (in my review unit) and the Flow X13 laptop. My fan keeps the GPU cool.
Performance: Is it worth it?
I tested the combination of XG Mobile and Flow X13 computers in three modes:
- Flow X13 with internal graphics (GTX 1650 Max-Q)
- The Flow X13 + XG Mobile drives an internal display
- The Flow X13 + XG Mobile drives an external monitor
As can be seen from the charts below, the increase in performance is huge. We look at 2-3 times the performance in games and 10-15 times the performance improvement in tasks like 3D rendering, and this is driving the internal screen. Using an external monitor improves performance by an average of about 10 percent. Interestingly, video transcoding through the internal GPU was faster than more efficient when used externally. I assume that the overhead costs of additional processing degrade system performance in this task.
Based on these numbers alone, XG Mobile seems to be worth it. You have a feathered Ultrabook with you for light work, and when you want to play, you whip a small XG Mobile unit and plug it in. Win-win, right? Can be.
Verdict: It’s priced high, but I still think it’s worth it
There are two variants of XG Mobile and they are priced as follows:
- XG Mobile GC31R: RTX 3070 8GB – Rs 69,990
- XG Mobile GC31S: RTX 3080 16GB – Rs 1.39,990
I haven’t tested the 3070 version of XG Mobile, but from my experience testing 3070 and 3080 laptops, I can tell you right now that the 3080 is by no means twice as good as the 3070. high, I expect the performance gap between the two to rise to 20 percent. If you buy, skip the 3080.
If you’re someone looking for just the kind of experience that the Flow X13 + XG Mobile combination offers, I think it’s worth it. Personally, I’d rather just spend Rs 1.4 lax for a larger Zephyrus G15 than deal with the hassle of setting up an eGPU dock and the necessary desktop, but that’s just me.
When it comes to eGPU solutions, I think Asus ’XG Mobile is one of the simplest, most uncompromising and game-centric models.
I like what Asus does here, and while I’m still not a fan of eGPUs in general, I can respect the design and design work that went into creating a system like XG Mobile, and I hope to see more such models in the future.
Note: XG Mobile is currently only compatible with the Flow X13 laptop. Asus tells me they are looking to expand UI support in the near future.