- ✓Excellent build
- ✓High-quality 12.5-inch screen
- ✓USB 3.0 support
- ✕Disappointing battery life
- ✕No full-size SD card slot
- ✕Keyboard uses Bluetooth connection
ASUS's line of Windows-based Transformer Book Chi hybrid tablets comes in three sizes: the tiny 8.9-inch T90; the 10.1-inch T100; and the 12.5-inch T300. Our T300 Chi review unit came with Windows 8.1, which we upgraded to Windows 10 during the test period.
The Transformer Book T300 Chi starts at £600 (inc. VAT; £500 ex. VAT, or $699) with a full-HD screen and 4GB of RAM; our review unit, with a higher-resolution (2,560 by 1,440) screen and 8GB of RAM costs around £800 (inc. VAT; £615 ex. VAT, or $899).
ASUS knows how to do good design, and over the years has shown this off to good effect with the Transformer Book range. It's difficult to find fault with either the T300 Chi tablet or its detachable keyboard dock.
Some tablet/laptop hybrids have a top-heavy tablet section that can cause the system to topple when you prod the screen. This is the result of all the computing components being packed into the screen section (in laptop mode). ASUS has overcome this problem by making the tablet and keyboard sections almost equal in weight -- 720g versus 700g respectively. This does result in a relatively weighty 1.42kg overall, but we'll take that considering the added benefit of a solid metal chassis for both sections.
The deep blue chassis is bound in aluminium all round, with a narrow silver frame around the back edge of the tablet (the lid in laptop mode), the top of the keyboard section and the touchpad. It is a neat design feature that we've seen before.
The two chassis sections are both made from single sheets of aluminium. That means there are no visible joins and no screws. It helps make this an extremely thin device measuring no more than 17mm as a single unit.
Because the lid and keyboard are the same size (318 by 192mm) they fit pretty flush when the Transformer Book T300 Chi is closed. There's no indent on the keyboard or tablet to help lever the two sections apart, and we needed to use both hands to open the device, which became rather irritating over time.
The dock mechanism, on the other hand, is superb. Two wide metal fingers on the keyboard section fit into slots on the tablet to ensure correct positioning, with the two sections held together entirely by magnets. These are strong enough to allow you to lift the whole device up by the tablet/lid without the keyboard falling away. It's very simple, and very efficient.
It's a shame that ASUS has not been able to devise the hinge to allow a full 360-degree pivot. As it is, the screen maxes out just past 90 degrees, so the Transformer Book T300 Chi can't be used in (270-degree) 'tent' mode, or with the screen flat on the desk. This arguably makes it less flexible than, say Lenovo's Yoga 3 Pro with its fully rotating screen.
Then again, those rotating screen devices don't let you leave the keyboard at home if you want to travel light --, and you can, in fact, set the tablet down face up while disconnected from the keyboard and still work as if they were docked, because the connection between the two uses Bluetooth rather than a wired link through the docking mechanism.
The Bluetooth link is toggled by a small slider button on the keyboard section, and it worked seamlessly for us. But it does mean the keyboard has to be separately charged. There's no low power light indicator on the keyboard, although a light does come on when you are charging it.
The keyboard is charged by USB, and you can use a standard USB AC adapter. ASUS also provides a cable to connects the charge port on the left side of the keyboard to the USB 3.0 port on the right side of the tablet, so the keyboard can charge from the tablet. It'll do this even when mains power is not connected. So, if you happen to leave home without a fully charged keyboard and it dies on you, it's possible to give it some juice -- so long as you're carrying a charge cable.
Because the keyboard doesn't have a powered link to the tablet it can't provide any ports or connectors. ASUS's desire to keep the tablet thin also means there's no full-sized USB port: instead, you get a dongle for the Micro-USB 3.0 port that gives you two full-size USB ports. That's OK, but it is something else you need to remember to carry around.
The Transformer Book T300 Chi loses out to more conventional ultrabooks because it also lacks a full-size SD card slot. There's a Micro-SD card slot on the tablet, so we could transfer files from our camera as we use Micro-SD with an SD converter in the camera, but it's fiddly and we're not sure we'd want to do it regularly. The fiddliness is more annoying because when the tablet and keyboard are docked the Micro-SD card slot sits on the bottom of the tablet where it's impossible to access unless you undock, close the lid or lift up the whole docked unit.
In addition to the ports and connectors already noted, the T300 Chi has a Micro-HDMI connector, a combo headset/microphone jack, twin speaker grilles, a volume button and a Windows button. Plus the on/off button and power input, of course.
The 12.5-inch tablet's 2,650 by 1,440-pixel resolution (235ppi) delivers plenty of detail for web browsing and video viewing, making the T300 Chi a good vehicle for on-device presentations. The speakers deliver loud enough sound too, while the IPS panel has very good viewing angles.
The screen's very reflective finish won't be to everyone's taste, though, and some may find that a fair bit of zooming is required when working with documents and spreadsheets because of its high pixel density.
Having grumbled about the keyboard section's connectivity, we've got nicer things to say about its usability. The keys are responsive and very well sized - touch typing at speed was not a problem. The touchpad is very small but it is responsive. It sometimes felt a bit laggy thanks to its Bluetooth connectivity, particularly on first use after a break.
The Transformer Book T300 Chi is built around an Intel Core M-5Y71 processor with 8GB of RAM. It whizzed along nicely for us -- both before and after we updated Windows 8.1, which it shipped with, to Windows 10.
If need to carry a lot of data on-board, you may be put off by the built-in 128GB of SSD storage. After upgrading to Windows 10 we were left with just 74GB for any programs and data we might want to install. We were able to read data easily from a USB-attached device -- but of course, that's yet another item to carry around.
As with many ultra-thin laptops and hybrids there's no wired Ethernet connection, so you'll have to rely on the T300 Chi's 802.11ac wi-fi to connect to networks in the office and on your travels.
The biggest drawback with the Transformer Book T300 Chi is undoubtedly its battery life. According to ASUS, the 32Wh battery is good for eight hours of video playback, or seven hours of web browsing or music playback. However, with our usual mix of workloads (document creation/editing, web browsing, email and occasional video playback), we regularly needed to recharge the system by mid afternoon.
The ASUS Transformer Book T300 Chi looks fantastic, and its magnet-based docking mechanism is impressively reliable. The Core M processor delivers enough power for mainstream workloads, and the high-resolution screen is great for both work and downtime (if you can live with its reflective coating).
However, the keyboard dock's reliance on Bluetooth rather than a wired connection has its drawbacks, while the lack of both full-size SD and USB is irritating. Battery life, in particular, is disappointing.
Overall, this is less the neatly integrated hybrid we've come to expect from the Transformer range, and more a decent tablet with a bundled Bluetooth keyboard.
|LCD Backlight Technology||LED backlight|
|Diagonal Size||12.5 in|
|Diagonal Size (metric)||31.8 cm|
|Native Resolution||1920 x 1080|
|Operating System||Windows 8.1 64-bit Edition|
|Features||hard drive password, security lock slot (cable lock sold separately)|
|Compliant Standards||A-Tick, BSMI, C-Tick, CCC, FCC, RoHS, TUV, UL, WEEE|
|Clock Speed||800 MHz|
|Number of Cores||Dual-Core|
|Wireless Protocol||802.11a/b/g/n, Bluetooth 4.0|
|Data Link Protocol||Bluetooth 4.0, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n|
|Run Time (Up To)||8 hour(s)|
|Product Line||ASUS Transformer Book T300 Chi|
|Installed Size||4 GB|
|Type||Windows 8.1 64-bit Edition|
|Nominal Voltage||AC 120/230 V|
|Frequency Required||50/60 Hz|
|ENERGY STAR Certified||Yes|
|Service & Support|
|Type||1 year warranty|
|Service & Support Details|
|Type||accidental damage coverage, limited warranty|
|Full Contract Period||1 year|
|Dimensions & Weight|