It's been well over two years since ASUS announced its original ZenBook Pro, and while it received a spec bump late last year, it's about time for the company to revamp its premium desktop replacement line. Announced at the "Edge of Beyond" event ahead of Computex, the new ZenBook Pro UX550 once again dons a 15.6-inch 4K touchscreen behind the spin-metal lid, except this time it comes with Intel's top Kaby Lake option plus an NVIDIA GTX 1050 Ti graphics chip (with 4GB DDR5 VRAM). More notably, at 18.9mm thick and 1.8kg heavy, the UX550 is one of the most portable laptops in its class, beating the Dell Inspiron 15 7000 (25.44mm, 2.62kg) and Acer Nitro 5 (26.75mm, 2.7kg) which pack similar specs (except for their lack of 4K display option), while almost matching the smaller 14-inch Razer Blade (17.9mm, 1.86kg).
Gallery: ASUS ZenBook Pro UX550 | 9 Photos
Compared to its predecessor, the UX550 is able to make better use of its 4K display thanks to its quad-core Kaby Lake CPUs: both the top-tier Core i7-7700HQ (2.8GHz to 3.8GHz; 8 threads, 6MB cache) and the Core i5-7300HQ (2.5GHz to 3.5GHz; 4 threads, 6MB cache) feature dedicated 4K HEVC support, meaning they can process 4K video more efficiently. The UX550 has swapped one of the old USB Type-A ports for a second Type-C port next to the full-size HDMI 1.4 port, and with both Type-C ports supporting the Thunderbolt 3 spec (up to 40 Gbps), this laptop can handle dual 4K video output and power delivery.
The laptop's own 4K display has the same 72-percent NTSC gamut plus 178-degree viewing angle as before, though this time it has a slimmer 7.3mm bezel, which has helped shave 18mm off the previous body width. But there is a trade-off: ASUS decided to remove the numeric keypad, likely because it thinks not many people need this feature these days. Another downside -- though probably unrelated -- is that the old full-size SD card slot is now just a microSD slot, which is a nuisance for people like me who still use SD cards in our cameras.
On a brighter note, the UX550 has a denser battery with a whopping 12 to 14 hours worth of juice -- almost doubling that of the older model; and its quick charging can take it from zero to 60 percent in just 49 minutes. It can be configured with up to 16GB of DDR4-2400 RAM and up to 1TB of PCIe x4 SSD. There's also a new dual-fan cooling system to keep the CPU and GPU well-behaved. Another nice upgrade is the Harman/Kardon-certified quad-speaker audio system -- one driver on each side of the backlit keyboard (with 1.5mm key travel) and two beneath the trackpad. Speaking of, the multitouch glass trackpad has gained a fingerprint reader at the top right corner.
ASUS has yet to reveal the prices for the UX500, but given that it's a performance device, it'll definitely be asking for more money than its ZenBook and VivoBook siblings. What we do know is that it's launching with either Windows 10 Pro or Windows 10 Home in July this year, so stay tuned.
Update: And there we go: It starts at $1,299.
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