Many consider Razer the Apple of gaming laptops. And if Apple made gaming laptops, they would probably look a lot like Razer's.

The point is moot, of course, because Apple does not make gaming machines. But a real comparison between the hardware of both is now a reality with the new Razer Blade Stealth, a Windows ultrabook that rivals the Apple MacBook Air.

The 12.5-inch Stealth weighs 1.25kg, or around 100g less than the 13.3-inch MacBook Air. At 13.1mm, the Stealth is thinner than the 17mm Air.

Despite its sleek profile, the Stealth feels as rigid as the MacBook Air, thanks to its unibody aluminium chassis. But its matte black finish is quite the fingerprint magnet and picks up grease easily.

Its most unusual feature is the keyboard backlight, dubbed Chroma. Each individual key can be customised to have a different backlight colour, with up to 16.8 million shades to choose from.

Tweaking the backlight is done via Razer's Synapse software app. There are various presets that let you enable special visual effects, such as a wave-like effect that cycles through multiple colours from one end of the keyboard to the other. In addition, you can synchronise the backlight with a Razer Chroma-branded gaming keyboard or mouse plugged into the Stealth's USB 3.0 port. The result: a visual spectacle that is almost hypnotic.

The Razer Synapse app can also be used to create game macros and adjust other gaming-related settings, such as disabling the Windows logo key to prevent users from accidentally pressing the key during a gaming session.

But I am not a fan of the app's cloud-based design that requires users to log in, at least for the initial setup, simply to change keyboard and mouse settings.

The Stealth has a lush and rich 2,560 x 1,440 pixel touchscreen that offers wide viewing angles. But its bezel is relatively thick compared with the ultra-slim bezel on new laptops, such as the Dell XPS 13.

For those who desire a sharper display, Razer offers a 4K (3,840 x 2,160 pixel) display option for the Stealth for an additional $350. This 4K display is said to have 100 per cent coverage of the Adobe RGB colour space, making it suitable for photo-editing.

The Stealth does not have a dedicated graphics chip, relying instead on the built-in graphics of its Intel Core i7 processor. It will run casual or older games, but it is not fast enough for newer titles.

But the Stealth's graphics performance can be enhanced with an external graphics dock, called the Razer Core. This dock, which connects to the Stealth's Thunderbolt 3 port, supports a desktop-class graphics card that is sold separately. It also has Ethernet and USB ports.

In other words, the Razer Core dock turns the Stealth ultrabook into a gaming desktop. This idea is not new - the Dell Alienware Graphics Amplifier does something similar, though with a proprietary cable.

Razer has not announced the local pricing and availability of the Core, but it is selling at US$499 (S$671) in the United States.

Battery life could be better - the Stealth lasted 5hr 41 min in our video-loop test at full brightness and volume.

At $1,799, the Razer Blade Stealth compares well against the Dell XPS 13 ($1,799, a slower CPU, less RAM and storage) and the Apple MacBook Air ($1,828, a lower-resolution screen)

The cheaper HP Envy 13 ($1,699) has similar specs as the Stealth, although it does not have the Stealth's fancy keyboard backlight.

• Verdict: A premium ultrabook with the potential to become a true gaming machine with the right accessory.