Toshiba KIRAbook (KIRA-101) Ultrabook Review

There's no accounting for taste; it is up to the reader to decide whether the black and silver-colored casing is stylish or boring. Fact is that the first quality impression is very high: Brushed magnesium surfaces adorn both the casing and lid, the display is protected by scratch-proof Concore Glass from Corning. The extremely narrow display bezel is especially noticed in this relation. Depending on the side, it only has a width of 1.1 to 1.7 centimeters. That allows for an extremely compact surface area on par with a conventional 12-inch laptop. But the height of almost 20 millimeters does not set new standards. However, the ultrabook looks slimmer due to its wedge-shape design.

Owing to the generous use of light metals, Toshiba managed to keep the weight below 1.3 kilograms without affecting stability much. Particularly the base proves to be very rigid and barely warps even when using high force. The screen's thin build is noticed even more; we would appreciate a somewhat better stiffness here. The corresponding hinges are pulled agreeably tight (both hands needed for opening) and they are quite accurate, which reduces annoying wobbling when making touch inputs.

Finally, we look at the build quality, where there are only few details that can be reproached. For example, some gaps of the two-part base unit could be marginally smaller - being a bit fussy in this price range is allowed.

A conventional Philips screwdriver is the only tool needed for opening the casing that is secured with a total of 11 screws on the underside. The mSATA SSD and Wi-Fi module can be replaced, and the battery fixed with screws could principally also be exchanged after removing the base plate. However, the working memory and CPU are soldered (note: all Haswell ULV models are only available as BGA versions).

Warranty

Toshiba includes a two-year warranty ex-factory for customers from Austria and Germany. It can be upgraded for a relatively low price. For example, an upgrade to a total of 3 years costs 69 Euros (~$94), and 109 Euros (~$149) is charged for 4 years (both RRP) - we believe that is reasonable.

We first want to look at the image quality. The IPS screen made by Sharp (LQ133T1JX03) can regain a few points. The black level of only 0.17 cd/m² ascertained in maximum brightness adds up to a fabulous contrast ratio of 1367:1. For comparison: Neither Dell's XPS 13 (687:1) nor Apple's MacBook Pro Retina 13 (900:1) can compete with that; only the Asus Zenbook UX301 (2138:1) remains unrivaled.

Toshiba promises the buyer a factory-calibrated screen and consequently an especially accurate color reproduction. The result is impressive. With a DeltaE of just 2.5 (ColorChecker) and 2.55 (Grayscale), the Kirabook belongs to the best devices of its category. That is a real purchase incentive primarily for amateur photographers and image editors, although the competition featuring an apple is still a bit better here.

Compared with other IPS screens, our review sample is a bit more sensitive to side views. A subtle, yet visible grayish cast covers the image from an angle of approximately 20 degrees vertically. This could be due to the touchscreen layer and/or the Concore Glass. Apart from that, the image is mostly true and always well-legible.

The "U"-series of the Haswell architecture designed for ultrabooks is divided into two different model lines that are specified with a TDP of either 28 or 15 watts. While Apple, and some Asus models, feature the faster 28 watt chips, an energy-efficient Core i7-4500U clocks in the Kirabook. The dual-core's base rate of 1.8 GHz is consequently quite low, and a strong Turbo of up to 3.0 GHz (2 cores: 2.7 GHz) is to compensate for that. Hyper-Threading, alongside many other features that can be studied in our database, is for additionally improving the performance depending on the application.

Toshiba opted against installing an additional GPU, and thus the HD Graphics 4400 (200 - 1100 MHz) takes care of all graphic tasks. We will examine whether the performance reserves are sufficient for at least basic games based on various benchmarks.

The buyer does not have the usual choice or configuration options in terms of memory configuration - 8 GB of working memory and a 256 GB SSD are invariably specified here. According to the matching results of different tools, the RAM only operates in the DDR3L-1333 mode, which should not cause any major losses owing to the dual-channel bus.

Despite its considerably more energy-efficient processor, the Kira 101 easily keeps up with both the Zenbook UX301 (Core i7-4558U, 28 watts) and MacBook Pro Retina 13 (Core i5-4258U, 28 watts) in our CPU benchmarks. The contenders can also only reap in an advantage of not quite 10 and 20% even in the multi-thread test of Cinebench R11.5, where the Core i7-4500U soon finds the limits of its TDP of only 15 watts. This difference is virtually unnoticed in routine use, particularly since the differences are again lower when single threads are loaded. Dell's XPS 13 (Core i5-4200U, 15 watts), which is also optionally available in a stronger Core i7 configuration, has to be satisfied with fourth place. Pleasing: The Toshiba does not artificially throttle in battery mode; clock rates and benchmark scores remain stable even without the power supply.

Unlike Asus and Apple, who use a RAID0 array (Zenbook) or a fast PCIe bus (MacBook Pro) to ensure faster transfer rates, a conventional SSD in mSATA format works in the Kirabook. The Toshiba storage device dubbed THNSNJ256GMCT is not available on the open market. However, we assume a strong relation with the models from the Q Series Pro (19-nanometer MLC-NAND).

The sequential transfer speeds settle to around 500 MB/s due to the limiting SATA interface. The drive is slightly above in read and a bit below this rate in write. Alongside the good scores in the practical 4K tests, the SSD is approximately on par with a Samsung PM841 or Crucial M500.

Unfortunately, we have to discourage any hopes of playing games in the WQHD screen's full resolution from the outset. The HD Graphics 4400 cannot render current titles with more than low to medium details in 1024x768 or, in rare cases, 1366x768 pixels. However, the HD Graphics 5000 of other 15-watt models does not offer a noticeable plus either. We would certainly ascribe that to the Iris Graphics 5100, but it does not calculate faster than a dedicated, entry-level accelerator, such as the GeForce GT 720M.

The slim magnesium casing's high thermal conductivity ensures that the chassis feels always exceptionally cool during low load. Our thermometer recorded temperatures of just 23 to 26 °C - that is an astonishingly low rate in view of the usually passive cooling. The temperatures measured after our one-hour stress test were just as convincing: Only one measuring point above the key slightly surpassed 40 °C. The ultrabook did not even get lukewarm otherwise.

The Core i7's sensor inside the casing recorded a maximum core temperature of 75 °C, which is far less than Intel specifies (100 °C). The reason that the CPU's clock rate nevertheless drops below the base speed of 1.8 GHz and settles to approximately 1.3 GHz is due to it reaching the TDP limit. It is largely claimed from the GPU that is allowed to clock with a consistently high 900 MHz when Prime95 and Furmark are performed simultaneously.

Good, but not good enough: Despite an overall convincing performance, Toshiba's Kira-101 does not reach a top spot in our ultrabook ranking list. The prospects are undeniably promising - as light as a MacBook Air, hardly slower than the MacBook Pro or Asus Zenbook UX301, topped with low emissions and impeccable input devices sound like a completed total package.

Nevertheless, Toshiba will have a hard time in justifying the exorbitant purchase price of approximately 1500 Euros (~$2054). The aforementioned Apple contenders cost roughly 150 Euros (~$205) less with comparable equipment but feature a better build and offer a longer battery runtime at the same time. The Kirabook also has to compete with Dell's XPS 13 in the Windows camp. Its higher brightness more than just compensates for the lower screen resolution. The brightness is probably our biggest point of criticism about the Kira-101 - an ultrabook that can only be used outdoors with restrictions barely does justice to its actual purpose. For this reason, we decided to deduct one percentage point from the final score. 

Notwithstanding this criticism, the Kirabook remains an outstanding ultrabook that certainly might earn a purchase recommendation in the course of future price cuts.