ASUS K42F Review

Laptop Mag Verdict

One of the first Core i5 notebooks offers jaw-dropping speed and Blu-ray playback in a comfortably portable package.


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    Blistering performance

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    Improved Intel HD graphics

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    Smooth Blu-ray playback

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    Crisp and bright display


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    Smudge-prone design

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    Mushy keyboard

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    Mediocre touchpad and mouse button

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Editor's Note: The K42F that Intel provided for review is not identical to what will be available for consumers. The most significant difference is the processor. The system we tested featured a 2.53-GHz Core i5-540M CPU, while the retail model features the 2.4-GHz 520M. Intel claims that the performance delta is within 3 and 5 percent. Other noteworthy differences include the hard drive (500GB for our config vs. 320GB for retail model), operating system (Windows 7 Ultimate vs. Home Premium), and the 802.11n wireless card model (Intel vs. Atheros). None of these differences should significantly impact performance. We reserve the right to change this notebook's rating once we test the retail version.

It blows away most other notebooks in every category when it comes to performance, and yet it weighs only five pounds. That's the power of Intel's Core i5 processor, the new chip inside the ASUS K42F (starting at $999). This CPU literally provides a turbo boost for mainstream laptops, along with technology that makes this dual-core machine ideal for serious multitasking. And with Intel's new Graphics Media Accelerator HD inside, this 14-inch machine can easily handle Blu-ray playback and many mainstream games. The K42F picks up fingerprint smudges too easily, and we're not fans of the narrow touchpad button, but overall it offers incredible power for the price without sacrificing battery life.


The first thing you'll notice about the 13.6 X 9.8 X 1.4-inch K42F is its attractive lid; it features a black finish with a subtle wavy pinstripe pattern. Upon lifting the lid, you'll find that the finish extends to the base of the system (except for the strip directly north of the keyboard) for a unified look. As with other glossy notebooks, the K42F collects fingerprints and smudges, which detracts from this system's initial appeal. Some may also be turned off by the plastic casing in an age where metal finishes are becoming all the rage. At 5.0 pounds, this notebook is quite totable, but it's a bit heavier than some similarly sized notebooks. The Lenovo IdeaPad Y450, for example, weighs just 4.6 pounds, and the Dell Studio 14z weighs just 4.4 pounds, but that laptop lacks an optical drive.

Keyboard and Touchpad

E-mailing friends and crafting Word documents was a breeze thanks to the K42F's spacious base and roomy palm rest area. The keyboard, however, could use some work; not only did we notice some flex, but the keys themselves had a somewhat hollow feel. On the plus side, a number of keys have special blue characters that allow you to launch programs when used in conjunction with the Fn key. Pressing Fn + space bar, for example, lets you cycle through power settings; Fn + F1 puts the system to sleep. It's a nice way to quickly accomplish simple tasks.

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The K42F has a large touchpad, but its glossy surface resulted in some friction, causing a halting motion in our finger as we dragged it across. However, navigating the desktop was better on this machine than the HP Pavilion dm3. More annoying is the single silver mouse button; it's too narrow for our tastes, and feels a bit cheap.

Display and Audio

Our Iron Man Blu-ray looked good on the K42F's 14-inch (1366 x 768) display. The reds and golds in Tony Stark's armor really popped, and night scenes had a suitable amount of darkness without overwhelming the visuals. The LCD's 16:9 aspect ratio means that the black bars at the top and bottom of the screen are smaller than usual while watching widescreen movies. Though the K42F's screen is glossy and kicks back reflections, they weren't overwhelming, and both horizontal and vertical viewing angles were very good.

A pair of Altec Lansing speakers with SRS audio boosting technology delivered passable audio, but lacked bass; automatic gunfire in Iron Man sounded less threatening than a bag of cooking popcorn. When we played Travis' "My Eyes" on, the maximum volume was good enough to fill a medium-size office, but it sounded tinny.

Ports and Webcam

The right side of the K42F features two USB 2.0 ports, VGA, HDMI, and a combo headphone/microphone jack; its left side houses an additional USB port and a Blu-ray reader. The front has a 3-in-1 memory card reader.

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The 1.3-megapixel webcam served up accurate colors and lifelike skin tones, which were only slightly cold when using Skype. While there was some motion blur when we moved quickly, it was better than average.

CPU and Hard Drive Performance

The 2.53-GHz Intel Core i5 CPU, along with 4GB of RAM, allowed the K42F to perform extremely well on our benchmarks. Like the Core i7 processor, the Core i5 CPU can overclock on the fly, up to 3.06 GHz. Moreover, hyperthreading technology allows the notebook's two cores to act handle four threads, much like a quad core processor. The laptop achieved a scorching 6,817 on PCMark Vantage, more than double the thin-and-light category average (3,164). This score also bested notebooks that cost more than twice as much, including Core i7 machines. For example, the Alienware M15x (1.73-GHz Intel Core i7-Q820) notched 6,543. The K42F also beat just about every other notebook equipped with a 2.53-GHz processor we've tested in the past year. The only exception was the Origin EON18, whose dual SSDs give it an advantage.

Here's how the K42F stacked up to other 2.53-GHz systems:

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ASUS K42FIntel Core i5-540M4GB RAM500GB HDD6817
Origin EON18Intel Core 2 Extreme QX93008GB RAM160GB SSD11039
Lenovo ThinkPad T400sIntel Core 2 Duo SP96002GB RAM128GB SSD5893
Alienware M17xIntel Core 2 Extreme Quad QX93008GB RAM1TB HDD5276
Fujitsu Lifebook T4410Inel Core 2 Duo P87002GB RAM160GB HDD3330
HP EliteBook 6930pIntel Core 2 Duo T94002GB RAM80GB SSD3123

The 5,400-rpm, 500GB Seagate Momentus hard drive inside the K42F duplicated a 4.97GB folder of mixed media at a rate of 27.8 MBps, which was well above the 20.8 MBps category average and the Dell Studio 14z's 18.5 MBps. The drive enabled the Windows 7 Ultimate operating system to boot in 1 minute and 4 seconds, which is 4 seconds longer than the average and 8 seconds longer than the Dell Studio 14z.

Graphics Performance

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While the ASUS K40 had an Nvidia GeForce G102M GPU (with 512MB of video memory), the K42F is equipped with the new integrated Intel GMA HD. While not as powerful as a high-end graphics card, it has a few new tricks up its sleeve, including 3D support for DirectX 10 and OpenGL 2.1, as well as hardware-accelerated decoding for Blu-ray.

The K42F notched a 3DMark06 score of 1,885, about 300 points higher than the K40 and over 400 points above the thin-and-light notebook average. However, the K42F's score was about 200 points below the Dell Studio 14z, which has a more powerful Nvidia GeForce 9400M G GPU. Still, when we output Iron Man to a 1080p 32-inch Samsung TV, Intel's GMA HD was able to keep up admirably; action remained smooth even at full screen, and colors were excellent.

Intel GMA HD graphics are good for entertainment and mainstream games, but you're not going to take it to any LAN parties. In World of Warcraft, the K42F managed a playable 33 frames per second at 1024 x 768, but it dropped to 9 fps at max resolution and effects. The notebook mustered just 13 fps when playing Far Cry 2 in its 1024 x 768 autodetect mode (where the average is 18 fps), and dropped to 5 fps at full resolution and graphics upped to Very High. The Dell Studio 14z saw significantly faster scores of 26 and 11 fps.

When we converted a 114MB MPEG-4 video file to AVI using HandBrake, the K42F took 3 minutes and 36 seconds to complete the task, approximately four minutes faster than the thin-and-light notebook average. Using Oxelon Media Converter, which takes advantage of the Core i5's multithreading capability, the same test took just 51 seconds. That's one of the best times we've seen, and beats out the Alienware M15x (54 seconds), ASUS G51J-A1 (1:01), Dell Studio 17 with Core i7 (1:19), and Origin EON18 (56 seconds).

Wi-Fi and Battery Life

The 802.11a/g/n Wi-Fi radio inside the K42F pushed data along at a rate of 20.8 Mbps when the notebook was placed 15 feet away from our access point, and 19.6 Mbps at 50 feet. These numbers are both in the vicinity of the category averages of 20.6 Mbps and 16.5 Mbps.

On our LAPTOP Battery Test, the K42F lasted 4 hours and 44 minutes, just above the thin-and-light notebook average (4:38) and almost an hour longer than the K40 (3:51, though that system was equipped with discrete graphics). However, the Dell Studio 14z, which also has discrete Nvidia graphics, lasted 5:25. You'll find other 13-inch and 14-inch notebooks that last even longer on a charge, like the ASUS UL30A (9:55), but they're powered by weaker Ultra-Low Voltage processors.

Green Testing

It took 2 hours and 1 minute to fully recharge the K42F's battery; during that time, the notebook used an average of 57 watts. For the LAPTOP Battery Efficiency Rating (the total amount of watts it takes to recharge divided by the battery life; the lower the score, the better), the system returned a score of 24.3 watts per minute of battery life--slightly more efficient than the K40 and the Dell Studio 14z (which both scored 26.4), and 1.3 watts lower than the thin-and-light average.

Software and Warranty

Bundled software includes Adobe Reader 9, Google Picasa 3, LifeFrame (for adding visual effects to webcam images), and Norton Internet Security (90-day trial). ASUS covers the K42F with a two-year global warranty with such extras as one year of accidental damage coverage, 30-Day Zero Bright Dot, two-way free standard overnight shipping, and 24/7 tech support. If you're curious about the quality of ASUS' support, check out how it fared in our annual Tech Support Showdown.


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There's no question that Intel's Core i5 processor is a breakthrough for notebook performance. And the ASUS K42F puts this technology to good use by delivering awesome performance for everyday tasks plus impressive multitasking power in a design that's easily portable. We also like the built-in Blu-ray player, bright screen, and nearly five hours of battery life. However, the design of this notebook doesn't quite live up to its high-octane components, especially when it comes to ergonomics. Overall, though, the K42F is one hell of a mobile speed demon.

Asus K42F Specs

BluetoothBluetooth 2.0
CPU2.53-GHz Intel Core i5-540M
Card Slots3-1 card reader
Company Website
Display Size14
Graphics CardIntel GMA HD
Hard Drive Size500GB
Hard Drive Speed5,400rpm
Hard Drive TypeSATA Hard Drive
Native Resolution1366x768
Operating SystemMS Windows 7 Ultimate (64-bit)
Optical DriveBD-R
Ports (excluding USB)VGA, Headphone, HDMI, Ethernet
RAM Upgradable to4GB
Size13.6 X 9.8 X 1.4 inches
USB Ports3
Video MemoryShared
Warranty/SupportTwo-year global, one-year accidental damage, 30-day Zero Bright Dot/24/7 toll-free phone
Weight5.0 pounds
LAPTOP Reviews Editor