Comparison Dell SE2717H 27 " black vs Dell P2717H 27 " black

The technology by which the monitor matrix is made.

— TN+film. The oldest and most common technology for manufacturing matrices. The original TN (Twisted Nematic) monitors have a low response time and low cost, but the image quality is average. So, the colour quality is not high, and the perfect black colour cannot be reproduced at all. In addition, the original TN technology provides relatively small viewing angles. To correct this situation, a special film is applied to the surface of the matrix. These matrices received the name "TN + film". Monitors with such a matrix are widespread and inexpensive. They are well suited for undemanding users both at home and in the office, and gamers will appreciate the fast response time.

— *VA(Vertical Alignment, options: MVA, PVA, Super MVA, Super PVA). A kind of transitional option between expensive and high-quality IPS and low-cost TN. Provide sufficiently high-quality colour reproduction, including black colour, viewing angles can reach 178°. The main disadvantage of VA matrices is the significant response time (especially for MVA monitors), due to which such monitors are relatively poorly suited for watching videos and dynamic games. This shortcoming is gradually being eliminated, and the latest models of VA monitors are approaching TN + film in respo...nse time.

— IPS. Initially, IPS technology was created for high-end monitors (in particular, "designer"), the key parameters for which were the quality of colour reproduction and a wide colour gamut. With all these advantages, the original IPS matrices also had a number of serious drawbacks — first of all, low response speed and impressive cost. Thus, many modifications of the IPS technology have been developed, designed to compensate for these shortcomings to one degree or another.

— OLED. Monitors with screens using organic light emitting diodes — OLED. Such LEDs can be used both to illuminate a traditional matrix, and as elements from which a screen is built. In the first case, the advantages of OLED over traditional LED backlighting are compactness, extremely low power consumption, backlight uniformity, as well as excellent brightness and contrast ratios. And in matrices, consisting entirely of OLED, these advantages are even more pronounced. The main disadvantages of OLED monitors are the high price (which, however, is constantly decreasing as the technology develops and improves), as well as the susceptibility of organic pixels to burn-in when broadcasting static images for a long time or pictures with static elements (toolbar, clock, etc.).

— QLED. Monitors built using quantum dot technology (QLED). This technology can be used in matrices of various types. It involves replacing a set of several colour filters used in classic matrices with a special thin-film coating based on nanoparticles, and traditional white LEDs with blue ones. This allows you to achieve higher brightness, colour saturation and colour quality at the same time as reducing the thickness and reducing power consumption. In addition, QLED is well suited for creating curved screens. The flip side of these benefits is the high price.

— QD-OLED. A kind of hybrid version of matrices that combine “quantum dots” (Quantum Dot) and organic light-emitting diodes (OLED) in one bottle. The technology takes the best from QLED and OLED: it is based on blue LEDs, self-luminous pixels (instead of external backlighting) and “quantum dots”, which play the role of color filters, but at the same time practically do not attenuate the light (unlike traditional filters) . Thanks to the use of a number of advanced solutions, the creators managed to achieve very impressive characteristics, significantly superior to many other OLED matrices. Among them are high peak brightness from 1000 nits (cd/m²), excellent contrast and black depth, as well as an expanded color gamut (over 120% of the DCI P3 gamut). Such matrices are found mainly in expensive advanced monitors with a large screen diagonal.

— AHVA. A type of matrix created by AU Optronics (a joint venture between Acer and BenQ) as a solution similar to modern IPS. Among the key advantages of this option over analogues is the almost complete absence of colour distortions at all viewing angles.

– PLS (Plane to Line Switching). This type of matrix was developed by Samsung engineers. It is based on the familiar IPS technology. According to some parameters, namely: the brightness and contrast of PLS exceeds IPS by 10%. The main goal of creating a new type of screens was to reduce the cost of the matrix, according to the developer, the production cost was reduced by 15%, which will positively affect the final price of monitors in comparison with IPS counterparts.

— IGZO. Technology introduced by Sharp in 2012. The key difference between IGZO and classic LCD matrices is that for the active layer (responsible for creating the image) it uses not amorphous silicon, but a semiconductor material based on indium gallium oxide and zinc oxide. This makes it possible to create screens with extremely fast response times and high pixel densities, and the technology is considered well suited for ultra-high resolution screens. With all this, the colour rendering characteristics allow the use of IGZO monitors even in the professional field, and the power consumption is very low. The main disadvantage of this option is the high cost.

— UV2A. An LCD display technology developed by Sharp and introduced in 2009. One of the key features of UV2A matrices is that they are based on liquid crystals that are sensitive to ultraviolet light. And it is UV radiation that is used as a control signal — it ensures that the crystals turn in the right direction to form an image. The technical features of such systems are such that the position of individual crystals can be controlled with extremely high accuracy — up to several picometers (with the size of the crystals themselves about 2 nm). According to the manufacturer, this provides two key benefits: no backlight "leakage" and improved light transmission with "open" crystals. The first allows you to achieve very deep and rich blacks, the second provides excellent brightness with low power consumption, and together these two features make it possible to create screens with a very high static contrast ratio — up to 5000: 1. At the same time, we note that the actual contrast characteristics in UV2A monitors can be noticeably more modest — it all depends on the features of a particular matrix and the characteristics that the manufacturer was able or considered necessary to provide.

— Mini LED IPS. A variation on the theme of the familiar IPS-matrix, which is illuminated by an array of reduced LEDs. The small caliber of individual light sources (of the order of 100-200 microns) makes it possible to form a much larger number of zones of controlled local dimming of the screen. Together, this delivers improved brightness, contrast, colour saturation, and black depth, and raises the bar for High Dynamic Range (HDR) technology.

— Mini LED VA. A variety of VA-matrices with a Mini LED backlight system. It consists of many tiny LEDs, which, due to their number, form many times more local screen dimming zones than standard canvases. As a result, Mini LED VA panels boast improved colour reproduction, impressive black depth, and multiple performance improvements in HDR content.

— Mini LED QLED. Behind the plane of the QLED panel in monitors with a Mini LED backlight system are thousands of miniature LEDs no larger than 200 microns in size, which divide the screen into a great many zones with controlled local dimming. They are individually dimmable, allowing full display of HDR content with bright light and deepest black levels.

Dynamic contrast provided by the monitor screen.

Dynamic contrast refers to the difference between the brightest white at maximum backlight intensity and the deepest black at minimum backlight. In this way, this indicator differs from static contrast, which is indicated with a constant backlight level (see above). Dynamic contrast ratio can be expressed in very impressive numbers (in some models — more than 100,000,000: 1). However, in fact, these figures are poorly correlated with what the viewer sees: it is almost impossible to achieve such a difference within one frame. Therefore, dynamic contrast is most often more of an advertising than a practically significant indicator, it is often indicated precisely in order to impress an inexperienced buyer. At the same time, we note that there are "smart" backlight technologies that allow you to change its brightness in certain areas of the screen and achieve a higher contrast in one frame than the claimed static one; these technologies are found mostly in premium monitors.

The colour depth supported by the monitor.

This parameter characterizes the number of shades that the screen can display. And here it is worth recalling that the image in modern monitors is based on 3 basic colours — red, green, blue (RGB scheme). And the number of bits is indicated not for the entire screen, but for each base colour. For example, 6 bits (the minimum colour depth for modern monitors) means that the screen is capable of producing 2 ^ 6, that is, 64 shades of red, green and blue; the total number of shades will be 64 * 64 * 64 = 262,144 (0.26 million). An 8-bit colour depth (256 shades for each base colour) already gives a total of 16.7 million colours; and the most advanced modern monitors support 10-bit colour, allowing you to work with more than a billion shades.

Screens with support for FRC technology are worth a special mention; nowadays, you can find models marked " 6 bit + FRC " and " 8 bit + FRC ". This technology was developed to improve picture quality in situations where the incoming video signal has a greater colour depth than the screen, such as when 10-bit video is fed to an 8-bit matrix. If such a screen supports FRC, the picture on it will be noticeably better than on a regular 8-bit monitor (although somewhat worse than on a full-fledged 10-bit monitor, but “8 bit + FRC” screens are much...cheaper).

High colour depth is important primarily for professional graphics and other tasks that require high colour fidelity. On the other hand, such features significantly affect the cost of the monitor. In addition, it is worth remembering that the quality of colour reproduction depends not only on the colour depth, but also on other parameters — in particular, colour gamut (see below).

The colour gamut of a monitor characterizes the range of colours that the screen is capable of reproducing.

This parameter is specified as a percentage, however, 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. Monitor specifications may specify which colour model is used for gamut (see below). If there is no such clarification, then, usually, we are talking about the sRGB model — it is accepted as a general standard for computer technology. In this case, the closer the colour gamut of the monitor is to 100%, the more accurately the colours on the screen will match the colours that were originally intended. Too little colour gamut results in a dull, faded image, and too much — unnatural and oversaturated. However, in fact, values from 90% to 110% are considered quite acceptable for most cases and do not lead to a noticeable deterioration in the image. In general, it is considered that “more is better than less”, and for a high-end monitor (especially professional) sRGB coverage should be 100% or higher.

The colour gamut of the monitor is based on the NTSC colour model.

Any colour gamut is indicated as a percentage, however, 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 monitor's capabilities, the better its colour reproduction.

Specifically, NTSC is one of the first colour models created back in 1953 with the advent of colour television. It is not used in the production of modern monitors, but is often used to describe and compare them. NTSC covers a wider range of colours than sRGB, which is standard in computer technology: for example, coverage of only 85% in NTSC gives about 110% in sRGB. So the colour gamut for this model is usually given for advertising purposes — as a confirmation of the high class of the monitor; a very good indicator in such cases is considered to be 75% or more.

— KVM switch. The presence of a KVM switch in the monitor - Keyboard, Video, Mouse. This module allows you to control two or more computers using one monitor, one keyboard and one mouse, quickly switching between different PCs (for example, a desktop computer and a laptop). A KVM switch improves productivity when you need to use multiple computers at the same time or one at a time and eliminates desktop clutter. To switch from one computer to another, just one click of the mouse in the proprietary software or a programmed button on the keyboard is enough.

— Light sensor. A sensor that monitors the brightness of ambient light. It is mainly used to automatically adjust the brightness of the monitor itself to the specifics of the situation: for example, if the room gets dark, the image on the screen can also be made dimmer, and under sunlight for normal visibility, the brightness should be high. This provides additional comfort for the user and also contributes to energy savings.

— Presence sensor. A sensor that detects the presence of a person in front of the screen. Most often used to automatically control sleep mode: if there is no one in front of the monitor for a certain time, the screen backlight turns off, and when the user returns, it turns back on. This contributes to energy savings and increases the life of the matrix. In addition, the sensor can b...e useful for more specific tasks — for example, to control the presence of an employee at the workplace.

— PBP (Picture by Picture). Possibility to display two "images" on the monitor at the same time — from two different sources, each of which is connected to its own video input. This feature can be very useful in cases where you have to work with two devices at the same time — for example, with a laptop and the main system unit. The image from both devices is usually displayed side by side. Note that for PBP to work effectively, the screen must be quite large, so this function is found mainly among monitors with the appropriate diagonal — from 27 "and above.

— Flicker Free. Brightness control technology that eliminates excessive screen flicker. The idea of this technology is to reduce the brightness of the image directly by reducing the brightness of the backlight (whereas in monitors without Flicker Free, the brightness is adjusted by turning the backlight on and off at a high frequency). Due to the absence of flicker, the load on the eyes and nervous system is reduced, and working with the monitor (especially for a long time) becomes more comfortable.

— AMD FreeSync. Monitor compatible with AMD FreeSync technology. As the name suggests, this technology is used in AMD graphics adapters — so it's worth looking for a monitor with this compatibility if your computer has an appropriate graphics card. And the general idea of FreeSync is to match the frame rate of the monitor and the frequency of the video signal from the graphics card. Such a need arises in the light of the fact that in some cases the frame rate of the video signal can “float” (this is especially true for modern games and other resource-intensive tasks); and a mismatch with the monitor's refresh rate can result in jaggies, jerks, and other artifacts. FreeSync avoids this.
Note that in this case we are talking about the original version of this technology — support for FreeSync Premium and Premium Pro is indicated separately, for these versions, see below. A similar solution from NVIDIA is called G-Sync; it is also described below.

— AMD FreeSync Premium Pro. The most advanced (at the beginning of 2020) version of the FreeSync technology described above, formerly known as AMD FreeSync 2 HDR. As the first name implies, one of the features of this version is HDR support. In addition, FreeSync Premium Pro claims a frame rate of at least 120 fps at Full HD resolution, as well as low frame rate compensation (LFC). The essence of this function lies in the fact that when the frame rate of the source video signal falls below the minimum frequency supported by the monitor, the same frame is displayed on the screen several times, which allows you to maintain the maximum smoothness of the “picture”. According to the creators, FreeSync Premium Pro works especially well in games; and many modern games are originally designed to work with this technology.

— AMD FreeSync Premium. An intermediate option between the basic AMD FreeSync technology and the advanced FreeSync Premium Pro. Both of these versions of the technology are described in more detail above; and FreeSync Premium does not have HDR support (unlike the Pro version), but works at the same frame rate (at least 120 fps at 1920x1080 resolution) and also uses LFC low frame rate compensation technology.

— NVIDIA G-Sync. A technology for matching the frame rate of the monitor and the frame rate of the video signal used in NVIDIA video cards. The need for such coordination arises due to the fact that in some cases the frame rate of the video signal can “float” (this is especially true for modern games and other resource-intensive tasks); and a mismatch with the monitor's refresh rate can result in jaggies, jerks, and other artifacts. A similar technology from AMD is called Freesync (see above).
Note that in this case it means support for the original G-Sync technology, which was originally incorporated during production. Support for the more advanced G-Sync Ultimate, as well as G-Sync Compatible compliance, are listed separately (see below).

— NVIDIA G-Sync Ultimate. A variation of the G-Sync technology described above, which provides not only for matching the frame rate with the graphics card, but also for a number of improved characteristics of the monitor itself. So, models with this marking necessarily support HDR (and according to a very high standard — not lower than DisplayHDR1000), and also have an extensive colour gamut, often measured by DCI P3 (see above for both). Most of these monitors are gaming monitors (see "Type").

— NVIDIA G-Sync compatible. This feature is indicated for monitors that were not originally designed for use with G-Sync technology (see above), but according to the results of testing, they turned out to be compatible with it. All such devices are models with the AMD FreeSync function (also described above), which were tested by nVIDIA and showed the ability to fully work with G-Sync as well (however, we emphasize that FreeSync support by itself does not yet guarantee compatibility with G-Sync) . Anyway, from the user's point of view, the difference lies in the fact that G-Sync Compatible monitors are much cheaper than their counterparts with G-Sync, but may be inferior to them in picture quality. This is due to the fact that these monitors do not undergo additional image quality tests that are required for devices with native G-Sync support. In addition, in G-Sync Compatible models, correct frame synchronization when working with NVIDIA video cards is guaranteed only if the graphics card is based on the GeForce GTX 10-series and GeForce RTX 20-series GPUs — these are the adapters that compatibility testing is carried out on.

— Adaptive Sync. Screen support for VESA Adaptive-Sync technology. The feature aims to synchronize the display's refresh rate with the GPU's frame rate to reduce latency, minimize artifacts, and eliminate visual tearing. Adaptive-Sync certified screens should run at a default refresh rate of 120Hz, but should be able to drop the frame rate down to 60Hz. The actual response time of such displays should be less than 5 ms. It is important to note that VESA Adaptive-Sync technology is only available for DisplayPort version 1.2a or later.

— CalMAN certification. The monitor has a CalMAN Verified certificate. This certification is given to high-quality screens after they have been tested and calibrated using CalMAN, a professional suite of software tools used for colour manipulation and sensor colour adjustment. The accuracy of these tools is such that even Hollywood filmmakers use them; and in the case of monitors, CalMAN certification is an additional sign of high quality — it means that the colours on such a screen will be displayed as faithfully as possible. Such models are intended mainly for professionals working with colour, as well as for connoisseurs of high-quality video content.

— Pantone certified. The presence of the monitor certificate "Pantone Validated" — that is, a certificate of compliance with the Pantone colour system (PMS). This is a professional colour system created by the company of the same name and widely used in design and printing. One of Pantone's basic ideas is that each colour should remain the same at all stages of work — from agreeing on a general idea to printing / releasing the final product; To do this, all shades covered by the system are assigned code names, which are used in the work. In the case of monitors, Pantone certification means that when working with materials and software tools that use a given colour scheme, the colours on the screen will match the actual Pantone hues as closely as possible. We emphasize that there is no question of perfect correspondence (LCD matrices are not physically capable of adequately displaying some shades); in addition, monitors with such certification may have different colour gamuts — both in percentage and in the systems used for designation (sRGB, Adobe RGB, DCI P3 — see above). However, even if the colour is beyond the capabilities of the screen, it will be displayed as accurately as possible. Therefore, for professional tasks associated with intensive use of Pantone, it is worth choosing monitors with official certification; An example of such tasks is the printing of image printing.

The screen is 90° rotatable on a stand, from landscape (horizontal) to portrait (vertical). The vertical orientation of the screen ( portrait mode) can be useful, for example, when working with large documents made in portrait orientation.

The ability to move the monitor screen up and down relative to the base. This feature is very convenient for adjusting the height of the screen — moving it on the mount is much easier than looking for a stand or resorting to other tricks.

a USB hub 2.0 is a set of additional USB ports on the monitor case, to which you can connect various peripherals (provided that the monitor is connected to the computer's USB port with a special cable). This equipment performs two useful functions. First, the hub increases the number of ports available for connection. Secondly, these connectors are located in close proximity to the user, literally at arm's length. However note that splitters are not well suited for connecting devices that require a lot of power via USB (for example, external hard drives without a separate power supply). This is due to the fact that the splitter “divides” the power coming from the computer port equally to all connected devices, and with a “loaded” hub, the power may not be enough at one moment.

Also note that the 2.0 standard is characterized by a bandwidth of 480 Mbps and has long been considered obsolete, but monitors with this interface are still being produced.