Comparison Acer Extensa 15 EX215-23 [EX215-23-R2EZ] vs Acer Aspire 3 A315-24P [A315-24P-R2WA]

The maximum brightness that a laptop screen can provide.

The brighter the ambient light, the brighter the laptop screen should be, otherwise the image on it may be difficult to read. And vice versa: in dim ambient light, high brightness is unnecessary — it greatly burdens the eyes (however, in this case, modern laptops provide brightness control). Thus, the higher this indicator, the more versatile the screen is, the wider the range of conditions in which it can be effectively used. The downside of these benefits is an increase in price and energy consumption.

As for specific values, many modern laptops have a brightness of 250 – 300 cd / m2 and even lower. This is quite enough for working under artificial lighting of medium intensity, but in bright natural light, visibility may already be a problem. For use in sunny weather (especially outdoors), it is desirable to have a brightness margin of at least 300 – 350 cd / m2. And in the most advanced models, this parameter can be 350 – 400 cd / m2 and even more.

The contrast of the screen installed in the laptop.

Contrast is the largest difference in brightness between the lightest white and darkest black that can be achieved on a single screen. It is written as a fraction, for example, 560:1; while the larger the first number, the higher the contrast, the more advanced the screen is and the better the image quality can be achieved on it. This is especially noticeable with large differences in brightness within a single frame: with low contrast, individual details located in the darkest or brightest parts of the picture may be lost, increasing the contrast allows you to eliminate this phenomenon to a certain extent. The flip side of these benefits is an increase in cost.

Separately, we emphasize that in this case only static contrast is indicated — the difference provided within one frame in normal operation, at constant brightness and without the use of special technologies. For advertising purposes, some manufacturers may also provide data on the so-called dynamic contrast — it can be measured in very impressive numbers (seven-digit or more). However, you should focus primarily on static contrast — this is the basic characteristic of any display.

As for specific values, even in the most advanced screens, this indicator does not exceed 2000: 1. But in general, modern laptops have a rather low contrast ratio — it is assumed that for tasks that require more advanced image characteristics, it is more...reasonable to use an external screen (monitor or TV).

The colour gamut of the laptop matrix according to the Rec.709 colour model or according to sRGB.

Colour gamut describes the range of colours that can be displayed on the screen. It is indicated as a percentage, but not relative to the entire variety of visible colours, but relative to the conditional colour space (colour model). This is due to the fact that no modern screen is able to display all the colours visible to humans. However, the larger the colour gamut, the wider the screen's capabilities, the better its colour reproduction.

Specifically, sRGB and Rec.709 are the most popular of today's colour models; they have the same range and differ only in the scope (sRGB is used in computers, Rec. 709 is used in HDTV). Therefore, the closer the colour gamut is to 100%, the more accurately the colours on the screen will match the colours that were originally intended by the creator of the film, game, etc. At the same time, note that such accuracy is not particularly needed in everyday use — it critical only for professional work with colour; and even in such cases, it is more convenient to buy a separate monitor with a wide colour gamut for a laptop, rather than looking for a laptop with a high-quality (and, accordingly, expensive) matrix.

The result shown by the laptop processor in the Passmark CPU Mark test.

Passmark CPU Mark is a comprehensive test that is more detailed and reliable than the popular 3DMark06 (see above). It checks not only the gaming capabilities of the CPU, but also its performance in other modes, based on which it displays the overall score; this score can be used to fairly reliably evaluate the processor as a whole (the more points, the higher the performance).

The connection interface used by the M.2 SSD installed in the laptop (see "Drive type").

One of the features of the M.2 connector and drives for it is that they can use two different connection interfaces: PCI-E (in one form or another) or SATA. We emphasize that this paragraph indicates the data of the SSD module; the connector itself may provide other interface options, including more advanced ones — see "M.2 connector interface" (for example, a drive with a PCI-E 3.0 2x connection can be placed in a connector that also supports the faster PCI-E 4.0 4x). However, anyway, the connection connector usually allows you to realize all the features of the installed drive; so this item allows you to quite reliably evaluate the capabilities of the standard M.2 module.

As for specific interfaces, nowadays you can mainly find the following options:

— SATA 3. The SATA interface was originally designed for traditional hard drives. The third version of this interface is the latest; it provides data transfer rates up to 600 Mbps. This is significantly less than PCI-E, and in general, very little by the standards of SSD drives. Therefore, M.2 connection using SATA is typical mainly for low-cost entry-level modules. However, even these media are generally faster than most HDDs.

— PCI-E. Universal interface for connecting internal peripherals. Provides generally faster speeds than SATA, making it better suited for SSD modules: theoretically, PC...I-E allows you to realize the full potential of SSDs, even the fastest. In fact, the supported data transfer rate may be different — depending on the version of the interface and the number of lines (data transmission channels). Here are the options most relevant for modern laptops:

• PCI-E 3.0 2x. Connection using 2 lanes PCI-E version 3.0. This version provides speeds of about 1 GB/s per line; respectively, two lines give a maximum of just under 2 GB / s.
• PCI-E 3.0 4x. Connection using 4 lanes PCI-E version 3.0. Provides a maximum speed of about 4 GB / s.
• PCI-E 4.0 4x. Connection using 4 lanes PCI-E version 4.0. In this version, the throughput, compared to PCI-E 3.0, has been doubled — thus, 4 lines give a maximum speed of about 8 MB / s.

Note that in the case of M.2 connectors, different PCI-E variations are usually quite compatible with each other — except that the connection speed when working with a "non-native" connector will be limited by the capabilities of the slowest component. For example, when connecting a PCI-E 3.0 4x SSD module to a PCI-E 3.0 2x slot, this speed will correspond to the capabilities of the connector, and when connected to PCI-E 4.0 4x, to the capabilities of the drive.

The interface of the main M.2 connector provided in the laptop.

In this case, the main slot is considered to be the one in which the SSD M.2 drive is installed (see "Drive type"). The interface of the drive itself is indicated separately (see above), and the interface of the connector is specified if the connector supports a more advanced type of connection than the device installed in it. An example is the following situation: the device itself works according to the SATA or PCI-E 3.0 2x standard (see "M.2 drive interface" above), and the connector on the board is capable of working with the PCI-E 3.0 4x interface.

Such information will be useful, first of all, for evaluating the possibilities for upgrading a laptop (with replacing a standard SSD module with a faster one). Nowadays, in this paragraph, you can mainly find the following options:

— PCI-E 3.0 2x. In fact, the most modest PCI-E standard found in M.2 ports of modern laptops: connection using 2 lanes of PCI-E version 3.0. This version provides speeds of about 1 GB/s per line; respectively, two lines give a maximum of just under 2 GB / s.

— PCI-E 3.0 4x. Connection using 4 lanes PCI-E version 3.0. Provides a maximum speed of about 4 GB / s.

— PCI-E 4.0 4x. Connection using 4 lanes PCI-E version 4.0. In this version, the bandwidth, compared to PCI-E 3.0, has been doubled — thus, 4 lines give a maximum speed of about 8 GB / s.

— PCI-E. Connection...via PCI-E, for which the manufacturer did not specify the details (version and number of lines).

Recall that in the case of M.2 connectors, different PCI-E options are quite compatible with each other — except that the speed will be limited by the capabilities of a slower component. In fact, this means that, for example, in an M.2 connector with a PCI-E 3.0 4x interface, it is quite possible to connect a drive for PCI-E 3.0 2x or PCI-E 4.0 4x; in the first case, the speed will be limited by the capabilities of the drive, in the second, by the capabilities of the connector.

The size of the M.2 SSD module (see "Drive Type") installed in the laptop. Specified in the format "width x length".

This parameter primarily allows you to evaluate the amount of space allocated for the drive, and the possibility of replacing it with a module of a different size. It is worth noting here that the M.2 standard itself allows several options for length and width, but boards with a width of 22 mm are most widely used. The length of such a board usually corresponds to one of the standard options: 30 mm, 42 mm, 60 mm, 80 mm and 110 mm.

In general, the installation of a shorter module of the same width (for example, 22x42 mm instead of 22x60 mm) does not cause problems, but the possibility of using larger components should be clarified separately — not every case allows the installation of M.2 drives with a larger one than the standard module , length. As for specific dimensions, the most common in modern laptops is M.2 22x80 mm SSDs: this size is guaranteed to allow you to change the “native” drive to almost any 22 mm standard module (except for the largest, 22x110 mm — and even for them there can be a place ). There are also smaller sizes — 22x60 mm, 22x42 mm and even 22x30 mm — but much less frequently. And here it is worth saying that the shorter the length of the SSD module, the smaller its capacity, usually.

Note that modern laptops also use M.2 modules of a different width — usually 16 mm with a length of 20 mm (16x20 mm). H...owever, this is a very rare option.

Maximum laptop operating time on a single battery charge, without recharging. In this case, usually, the operating time in the maximum energy saving mode is implied: disabled wireless modules, minimum screen brightness, a small load on the processor, etc. Accordingly, the time of actual work on a charge is usually noticeably less than this indicator. Nevertheless, it can be used both for a general assessment of the battery life of a laptop, and for comparing it with other models. And choose work laptop ( from 7 operation hours) or with more powerful battery (from 11 operation hours).

The main material from which the laptop case is made.

Modern laptops can use materials such as plastic (mostly matte plastic), aluminium, magnesium alloy, carbon fibre, and even glass. These materials are found both individually and in various combinations; the most common case is aluminium with plastic, but more specific combinations exist. Here is a more detailed description of the most relevant options:

— Matte plastic. Plastic with a matte (not shiny) surface is one of the most popular materials for laptop cases today. This is due, on the one hand, to low cost, on the other hand, to good practical characteristics. So, such a case can be given any colour and any pattern can be applied to it. The strength of plastic is lower than that of metals or carbon fibre, but it is usually more than enough for everyday use. And the light weight is not only an advantage in itself — it also allows you to make the walls of the case thick enough; as a result, plastic cases are often found even among shockproof models. As for the matte surface specifically, it itself looks dimmer than the glossy one, but it is not so prone to pollution. In particular, fingerprints and palm marks are practically invisible on it; and the scratches that plastic is subject to do not stand out as clearly as on gloss. A bright a...ppearance of the device can be given due to other design solutions — for example, keyboard backlighting (see above).

— Aluminium. From a practical point of view, aluminium alloys combine lightness and high strength; in addition, the metal conducts heat well, which improves the efficiency of cooling systems. Most of these cases have a characteristic grey tint, which looks quite stylish even without special coloring; and in some models, aluminium can additionally be given one or another colour. The main disadvantage of this material is a higher cost than plastic; as a result, it is used mainly in devices of the middle and top classes.

— Magnesium alloy. Such alloys surpass even the aluminium described above in strength, while they have a relatively small weight and excellent heat dissipation. However, this material is not cheap. Therefore, it is used quite rarely, and in its pure form — even less often; combinations of magnesium alloy with other, usually more affordable materials are more popular (see below for more details).

– Aluminium / plastic. Combination of plastic and aluminium elements in one housing. Usually, parts subjected to the greatest loads are made of metal, and the rest of the structure is made of plastic. These materials are described in more detail above, and their combination allows you to combine the advantages and partially compensate for the disadvantages. In particular, such combined cases are cheaper than all-metal ones and at the same time more reliable than plastic ones; in addition, they are easier to give a bright appearance than products made of aluminium or magnesium. This combination can be found even among relatively inexpensive laptops, although most metal-plastic models still belong to more advanced categories.

— Carbon fibre. Also known as "carbon". Usually, it is used in the form of a composite — a carbon fibre base is complemented by a plastic filler. Carbon belongs to the premium class materials: it is characterized by very high strength and at the same time low weight. A dark colour and a characteristic pattern on the surface give such cases a stylish appearance. However, carbon fibre is very expensive — much more expensive than even aluminium and magnesium, not to mention plastic. Therefore, such cases are a characteristic feature of top segment laptops. Also note that carbon does not tolerate point impacts; thus, and also to reduce cost, it is often used in combination with metals (see below for more details).

– Aluminium / magnesium alloy. Cases combining two types of metals. Usually, the main part of such a case is made of aluminium, and the individual, most important parts are made of magnesium. This allows some cost and weight savings compared to pure magnesium alloy cases, while at the same time providing greater strength and reliability than aluminium. A rarer and more specific variant is the 2-in-1 devices (see "Type"), where the top half is made of lighter aluminium (for easy portability) and the bottom half is made of durable magnesium.

– Aluminium / carbon fibre. Cases that combine elements of aluminium and carbon fibre. The specific set of parts from both materials can be different, but the upper side of the lower half of the device (where the touchpad and keyboard are) are most often made of carbon fibre. Such a surface not only looks good, but often also turns out to be more pleasant to the touch than aluminium. As for the general features, the combination of aluminium and carbon fibre can be used both for design reasons and for practical purposes — in order to compensate for the sensitivity of carbon to point impacts. In the latter case, the body elements that are most prone to such “troubles” are made of aluminium. In addition, replacing part of the carbon fibre with metal reduces the overall cost somewhat (but increases the weight).

— Magnesium alloy / carbon fibre. A combination similar to the aluminium with carbon described above, adjusted for the characteristics of magnesium alloys. Recall that such alloys, on the one hand, are stronger and more reliable than aluminium, on the other hand, they are somewhat heavier and more expensive. See also above for more details on the properties of carbon fibre. In general, this is a noticeably rarer option than aluminium + carbon: such cases are more expensive, while they have almost no significant advantages.

– Aluminium / glass. Quite a rare and even exotic option; in fact — the only case when glass is used as a material for laptop cases. It is found in certain premium-class models, including fashion ones. The aluminium case (see above) in such models is complemented by an overlay made of special high-strength glass — usually on the outer part of the lid, on the opposite side of the screen. Such glass resists scratches even better than a metal surface, and it further enhances the appearance. However, the practical advantages of such a combination, in fact, are limited to this, so that it is used mainly as an original design move.