The laptop's base plate is easy to remove without tools after releasing a total of eight screws. The fundamental maintenance options include expanding the working memory (two slots, one empty), replacing the SSD (2.5-inch or M.2 drive), and accessing the Wi-Fi and LTE module. It would also be possible to clean the fan and heat sink, but their accessibility is only limited without disassembling the laptop even further.

While the ProBook 640 G2 is available with a simple WXGA panel (1366x768 pixels) in other markets, HP presently only installs a high-resolution Full HD screen (1920x1080 pixels) in Germany. Alongside a screen diagonal of exactly 14.0 inches, this results in a pixel density of a pleasingly high 157 PPI that ensures a sharp yet not too small image reproduction. Users with normal eyesight should be able to recognize fine fonts and symbols well without increasing the scaling factor.

Besides the higher resolution, the Full HD panel also promises a stronger backlight. With a whole 304 cd/m² distributed very evenly over the entire screen area, our review sample, in fact, does an excellent job here and outruns all rivals by far. A small minus point is only found in the screen's PWM control (200 Hz, all brightness levels below maximum). This can cause headaches or dizziness in very sensitive users - the devices from Lenovo, Dell and Toshiba at least did not exhibit this issue in the tested configurations.

The ProBook is different than most rivals in another aspect: HP is the only manufacturer that does not rely on a high-quality IPS panel for its Full HD screen but normally installs the cheaper TN technology instead. The black level (0.61 cd/m²) and contrast ratio (516:1) are at least still quite decent when looking straight at the screen - but more about that later.

First a look at the screen's color reproduction: The panel displays a massive bluish tint and a correspondingly high DeltaE shift in delivery state. Calibrating improves the reproduction tremendously and the average DeltaE rates drop to an outstanding 1.1 (grayscale) and 1.7 (colors). Unfortunately, the available color space only covers the sRGB standard by not quite 75%, which is definitely too little for professional photo and image editing.

Finally, we will look at the 640 G2's biggest points of criticism: The insufficient viewing-angle stability. The aforementioned contrast and color accuracy rates are only valid when looking at the screen from an absolutely straight angle. The slightest shifts drastically distort the image impression. If HP used an IPS panel like other manufacturers, then this problem would be considerably less prominent - and the user would not have to permanently adjust the tilting angle according to the present seating position.

Slowly but surely, Intel's new Kaby Lake generation casts its shadow ahead - the first scions could already be presented as early as September. Until then, customers and manufacturers will have to be satisfied with the current Skylake product range. HP opted for the popular Core i5-6200U mid-range model. Its two cores clock at 2.3 to 2.8 GHz with Hyper-Threading (2 cores: 2.7 GHz). Being a ULV model, the 6200U is specified with a TDP of just 15 watts.

In addition to CPU cores, memory controller, and I/O interfaces, the chip (which is actually an MCM) also integrates a graphics unit dubbed HD Graphics 520. Being a medium GPU expansion stage (GT2), it clocks at 300 to 1000 MHz and has 24 execution units (EUs). The performance can even compete with some dedicated, low-end accelerators depending on the memory configuration.

However, the manufacturer only installs a DDR4-2133 module with a capacity of 8 GB ex-factory, which lowers the graphics performance slightly as a consequence of the resulting single-channel interface. A 256 GB M.2 SSD by Samsung serves as the storage device.

The ProBook does not have problems utilizing the Core i5-6200U's full Turbo Boost headroom and not only thanks to its bulky casing. A stable 2.8 GHz is achieved in the single-thread benchmarks, and it is still 2.7 GHz when both cores are loaded - in both AC and battery modes. The performance is correspondingly good. Devices furnished with the more expensive Core i5-6300U and Core i7-6500U models can only surpass the 640 G2 by approximately 5 to 10%. The Core i7-6600U, which is presently the top model, calculates a good 20% faster in ideal conditions (increased TDP limits). Although these differences are measurable, they are hardly noticed in routine use. HP has made a reasonable decision with the 6200U from a price-performance point of view.

The PM871 M.2 SSD by Samsung has a capacity of 256 GB, which is the medium-priced version with a SATA interface. With sequential transfer rates of approximately 500 MB/s in read and almost 300 MB/s in write, its performance is roughly on par with comparable drives by Toshiba or Liteon that are found, for example, in Lenovo and Dell laptops. In return, the PM871 has a slight lead on its rivals when dealing with smaller 4K files and multi-parallel accesses. Samsung's SSDs also have the reputation of being particularly reliable - thus, we can again congratulate Samsung for making a good decision in terms of components.