Comparison Lenovo IdeaPad S145 15 [S145-15IKB 81VD003RRA] vs HP 255 G7 [255G7 6BP88ES]

The technology by which the matrix of the laptop is made.

Matrices of the TN+film, IPS and *VA types are most widely used nowadays; less common are screens like OLED, AMOLED, QLED, miniLED, as well as more specific solutions like LTPS or IGZO. Here is a more detailed description of all these options:

— TN-film. The oldest, simplest and most inexpensive technology currently in use. The key advantages of this type of display are low cost and excellent response time. On the other hand, such matrices are not of high image quality: brightness, colour fidelity and viewing angles of TN-film screens are at an average level. These indicators are quite enough for working with documents, web surfing, most games, etc.; however, for more serious tasks that require a high-quality and reliable picture (for example, design or photo / video colour correction), such screens are practically unsuitable. Thus, TN-film matrices are relatively rare nowadays, mainly among low-cost laptops; more advanced devices are equipped with better screens, most often IPS.

— IPS (In-Plane Switching). The most popular type of matrix for laptops in the middle and top price range; however, it is increasingly common in low-cost models, and for trans...formers and 2-in-1 devices (see "Type") it is almost a standard option. Screens of this type are noticeably superior to TN-film in terms of the quality of the “picture”: they provide a bright, reliable and rich image that hardly changes when the viewing angle changes. In addition, this technology allows to achieve extensive colour gamuts in various special standards (see below) and is suitable for creating displays with advanced features such as HDR support or Pantone / CalMAN certification (also see below). Initially, IPS matrices were expensive and had a slow response time; however, nowadays, various modifications of this technology are used, in which these shortcomings are fully or partially compensated. At the same time, different modifications may differ in practical characteristics: for example, some are created based on the maximum reliability of the picture, others differ in affordable cost, etc. So it's ok to clarify the actual characteristics of the IPS screen before buying — especially if you plan to use a laptop for specific applications where image quality is critical.

— *V.A. Various modifications of matrices of the "Vertical Alignment" type: MVA, PVA, Super PVA, ASVA, etc. The differences between these technologies are mainly in the name and the manufacturer. Initially, matrices of this type were developed as a compromise between IPS (high-quality, but expensive and slow) and TN-film (fast, inexpensive, but modest in image quality). As a result, *VA screens turned out to be more affordable than IPS and more advanced than TN-film — they have good colour reproduction, deep blacks and wide viewing angles. At the same time, it is worth noting that the colour balance of the picture on such a display changes somewhat when the viewing angle changes. This makes it difficult to use *VA matrices in professional colour work. In general, this option is designed mainly for those who do not need perfect colour accuracy and at the same time want to see a bright and colorful image.

— OLED. Matrices based on the so-called organic light-emitting diodes. The key feature of such displays is that in them each pixel is a source of light in itself (unlike classic LCD screens, in which the backlight is made separately). This design principle, combined with a number of other solutions, provides excellent brightness, contrast and colour reproduction, rich blacks, the widest possible viewing angles and a small thickness of the screens themselves. On the other hand, laptop OLED matrices for the most part turn out to be quite expensive and “gluttonous” in terms of energy consumption, and they wear out unevenly: the more often and brighter a pixel glows, the faster it loses its working properties (however, this phenomenon becomes noticeable only after several years of intensive use). In addition, for a number of reasons, such screens are considered poorly suited for gaming applications. In light of all this, sensors of this type are rare these days — mostly in individual high-end laptops designed for professional colour work and with appropriate features such as HDR support, wide colour gamut and/or Pantone / CalMAN certification (see below).

— AMOLED. A kind of matrices on organic light-emitting diodes, created by Samsung (however, it is also used by other manufacturers). In terms of its main features, it is similar to other types of OLED matrices (see above): on the one hand, it allows you to achieve excellent image quality, on the other hand, it is expensive and wears out unevenly. At the same time, AMOLED screens have even more advanced colour performance combined with better power optimization. And the low prevalence of this technology is mainly due to the fact that it was originally created for smartphones and only recently began to be used in laptops (since 2020).

— MiniLED. Screen backlight system on a substrate of miniature LEDs with a size of about 100-200 microns (µm). On the same display plane, it was possible to increase the number of LEDs several times, and their array is placed directly behind the matrix itself. The main advantage of miniLED technology can be called a large number of local dimming zones, which in total gives improved brightness, contrast and more saturated colors with deep blacks. MiniLED screens unlock the potential of High Dynamic Range (HDR) technology, suitable for graphic designers and digital content creators.

— QLED. Matrices on "quantum dots" with a redesigned LED backlight system. In particular, it provides the replacement of multilayer colour filters with a special thin-film coating of nanoparticles. Instead of traditional white LEDs, QLED panels use blue ones. As a result, a set of design innovations makes it possible to achieve a higher brightness threshold, colour saturation, improve the quality of colour reproduction in general, while reducing the thickness of the screen and reducing power consumption. The reverse side of the QLED-matrices coin is an expensive cost.

— PLS. A type of matrix developed as an alternative to the IPS described above and, according to some sources, is one of its modifications. Such matrices are also characterized by high colour rendering quality and good brightness; in addition, the advantages of PLS include good suitability for high-resolution screens (due to high pixel density), as well as lower cost than most IPS modifications, and low power consumption. At the same time, the response speed of such screens is not very high.

— LTPS. An advanced type of TFT-matrix, created on the basis of the so-called. low temperature polycrystalline silicon. Such matrices have high colour quality, and are also well suited for screens with high pixel density — in other words, they can be used to create small displays with very high resolution. Another advantage is that part of the control electronics can be built directly into the matrix, reducing the overall thickness of the screen. On the other hand, LTPS matrices are difficult to manufacture and expensive, and therefore are found mainly in premium laptops.

— IGZO. An LCD technology that uses a semiconductor material based on indium, gallium, and zinc oxides (as opposed to more traditional amorphous silicon). This technology provides fast response time, low power consumption and very high colour quality; it also achieves high pixel densities, making it well-suited for ultra-high resolution screens. However, while such displays in laptops are extremely rare. This is explained both by the high cost and by the fact that rather rare metals are used in the production of IGZO matrices, which makes large-scale production difficult.

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 colour gamut of the laptop matrix according to the Adobe RGB colour model.

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.

The Adobe RGB colour model was originally developed for print applications; the range of colours covered by it corresponds to the capabilities of professional printing equipment. Therefore, theoretically, the extensive coverage of this model will be useful to those involved in the design and layout of high-end printed products. However most laptop screens have very limited Adobe RGB values, rarely exceeding 74%; however, you can also find high-end models where this figure approaches 100%. Of course, the cost of such laptops will also be appropriate; therefore, it makes sense to pay attention to them, first of all, when the ability to work with colour “on the go” is of key importance. If this is to be done in one place, it may be more justified to buy a separate monitor with a wide colour gamut (especially since a monitor with such characteristics is easier to find than a laptop).

Each series combines chips that are similar in general level, purpose, and often also in individual specific features. Moreover, most series include processors of several generations at once, which can differ significantly in actual characteristics. It is worth noting that until recently laptops were equipped almost exclusively with processors from AMD or Intel - until in 2020 Apple introduced its own chip Apple M1 (with updated versions Apple M1 Pro and Apple M1 Max), Apple M2 (2022) with powerful chips M2 Pro, M2 Max and Apple M3, M3 Pro, M3 Max (2023). At the moment, the following series are mainly relevant in laptops:

— AMD Ryzen 3. The most inexpensive series of AMD chips in the Ryzen family (Ryzen 3, Ryzen 5, Ryzen 7 and Ryzen 9) using the Zen microarchitecture. In terms of the general design, Ryzen 3 is similar to its older brothers, but half of the computing cores are deactivated. However, it is quite advanced and is found even in ultrabooks.
...> — Ryzen 5. The second series based on Zen architecture is a more affordable alternative to Ryzen 7 chips. Ryzen 5 chips have somewhat more limited performance characteristics (in particular, a lower clock frequency and, in some models, L3 cache size). Otherwise, they are completely similar to the “sevens” and are also positioned as high-performance chips for gaming and workstations. See "Ryzen 7" below for more details.

- Ryzen 7. The first series of processors from AMD, built on the Zen microarchitecture. It was introduced in March 2017. In general, Ryzen chips (of all series) are promoted as high-end solutions for gamers, developers, graphic designers and video editors. One of the main differences between Zen and previous microarchitectures was the use of simultaneous multithreading, due to which the number of operations per clock was significantly increased at the same clock frequency. In addition, each core received its own floating-point calculation unit, the speed of the first level cache increased, and the L3 cache capacity in Ryzen 7 chips is 16 MB as standard.

— Atom. Processors specifically designed by Intel for mobile devices (including smartphones). They are mainly used in ultra-compact laptops.

— Core M. Processors designed for portable equipment (in particular, ultra-compact laptops) and characterized by extremely low heat generation, allowing the use of passive cooling systems. They were introduced in 2014 as the first serial chips based on the 14 nm process technology.

— Celeron. The most budget series in the modern line of desktop processors from Intel. However, the latest generations come with integrated graphics.

— Pentium. Budget desktop processors from Intel, slightly superior in performance to Celeron, but not up to the Core i3. Also carry integrated graphics.

— Processor. The entry-level processor line that precedes the Core i3 family in the modern Intel hierarchy. Such chipsets are found in entry-level laptops designed for everyday household or office use, as well as undemanding games.

- Core i3. A series of entry-level and mid-level processors, the most budget series in the Core ix family; however, it outperforms the Pentium and Celeron series.

— Core i5. A series of mid-range processors, both in general and in the Core ix family. The architecture is dual- or quad-core, they have a third-level cache, and many models are also equipped with a built-in graphics chip.

— Core i7. A series of productive processors; before the advent of i9 was the most advanced in the "Core i" family. Core i7 chips have at least 4 cores, large level 3 cache and integrated graphics.

— Core i9. Top-level processors released in 2017; the most powerful line of consumer-grade laptop processors at the time of its introduction, displacing Core i7 chips from this position. They have from 6 cores and a volume cache of level 3.

— Apple. A series of processors from Apple, which debuted in November 2020 along with the release of the next generations of MacBook, MacBook Air and MacBook Pro. In the initial configurations, they are equipped with 8 cores - 4 productive and 4 economical; the latter, according to the creators, consume 10 times less energy than the former. This, combined with the 5 nm process technology, has made it possible to achieve very high energy efficiency and at the same time performance. It is also worth noting that the processors of this series are made according to the system-on-chip scheme: a single module combines a CPU, a graphics adapter, RAM (in the first models - 8 or 16 GB), an NVMe solid-state drive and some other components (in particularly Thunderbolt 4 controllers).

The specific model of the processor installed in the laptop, or rather, the processor index within its series (see above). Knowing the full name of the processor (series and model), you can find detailed information on it (up to practical reviews) and clarify its capabilities.

The code name for CPU installed in the laptop.

This parameter characterizes, first of all, the generation to which the processor belongs, and the microarchitecture used in it. At the same time, chips with different code names can belong to the same microarchitecture/generation; in such cases, they differ in other parameters - general positioning, belonging to certain series (see above), the presence / absence of certain specific functions, etc.

Nowadays, the following code names are relevant in Intel processors: Coffee Lake, Comet Lake, Ice Lake, Tiger Lake, Jasper Lake, Alder Lake, Raptor Lake (13th Gen), Alder Lake-N, Raptor Lake (14th Gen), Meteor Lake (Series 1), Raptor Lake (Series 1). For AMD, the list looks like this: Zen 2 Renoir, Zen 2 Lucienne, Zen 3 Cezanne, Zen 3 Barcelo, Zen 3+ Rembrandt, Zen 3+ Rembrandt R, Zen 2 Mendocino, Zen 3 Barcelo R, Zen 4 Dragon Range, Zen 4 Phoenix. Detailed data on different code names can be found in special sources.

The clock speed of the processor installed in the laptop (for multi-core processors, the frequency of each individual core).

Theoretically, a higher clock speed has a positive effect on performance, as it allows the processor to perform more operations per unit of time. However, in fact, the capabilities of the CPU depend on a number of other characteristics — primarily on the series to which it belongs (see above). It even happens that of the two chips, the more performant in the overall result is the slower one. With this in mind, it makes sense to compare by clock frequency only processors of the same series, and ideally, also of the same generation; and the laptop as a whole should be judged by the complex characteristics of the system, as well as by the results of tests (see below).