Comparison HP Z240 J9C05EA vs HP Z420 Workstation WM435EA

The form factor of a computer case characterizes, first of all, the internal volume. Main PC Form Factors:

— Midi Tower. A representative of the tower family (tower cases) of medium size — about 45 cm in height with a width of 15-20 cm, with the number of external bays from 2 to 4. Most popular for middle-class home PCs.

— Mini Tower. The most compact "vertical" case type, with a width of 15-20 cm, has a height of about 35 cm and (usually) less than 2 compartments with external access. Used mainly for office PCs that do not require high performance.

— Full Tower. The tower case is one of the largest form factors for PCs today: 15-20 cm wide, 50-60 cm high, with up to 10 externally accessible bays. Most often in this form factor running advanced high performance PCs

— Desktop. Enclosures designed for installation directly on the desktop. They often have the possibility of horizontal installation — in such a way that a monitor can be placed on top of the case — although there are also models that are installed strictly vertically. Anyway, "desktop" models are relatively small.

— Cube Case. Cases having a cubic or close to it shape. They can have different sizes and are intended for different types of motherboards, this point in each case should be clar...ified separately. Anyway, such cases have a rather original appearance, different from traditional "towers" and "desktops".

The model of the chipset used in the standard configuration of the PC.

A chipset can be described as a set of chips that provides the combined operation of the central processor, RAM, I / O devices, etc. It is this chipset that underlies any motherboard. Knowing the chipset model, you can find and evaluate its detailed characteristics; most users do not need such information, but for specialists it can be very useful.

The specific model of the processor installed in the PC, or rather, its index within its series (see "Processor"). The full model name consists of the series name and this index — for example, Intel Core i3 3220; knowing this name, you can find detailed information about the processor (characteristics, reviews, etc.) and determine how suitable it is for your purposes.

The number of cores in a complete PC processor.

The core is a part of the processor designed to process one stream of commands (and sometimes more, for such cases, see "Number of threads"). Accordingly, the presence of several cores allows the processor to work simultaneously with several such threads, which has a positive effect on performance. However note that a larger number of cores does not always mean higher computing power — a lot depends on how the interaction between command streams is organized, what special technologies are implemented in the processor, etc. So, only chips of the same purpose (desktop, mobile) and similar series (see "Processor") can be compared by the number of cores.

In general, single-core processors are practically not found in modern PCs. Mainly desktop chips of the initial and middle level are made dual-core. Four cores are found both in desktop CPUs of the middle and advanced class, and in mobile solutions. And six-core and eight-core processors are typical for high-performance desktop processors used in workstations and gaming systems.

Clock speed of the CPU installed in the PC.

In theory, higher clock speeds have a positive effect on performance because they allow the CPU to perform more operations per unit of time. However, this indicator is rather weakly related to real productivity. The fact is that the actual capabilities of the CPU strongly depend on a number of other factors - the overall architecture, cache size, number of cores, support for special instructions, etc. As a result, you can compare by this indicator only chips from the same or similar series (see “CPU”), and ideally, also from the same generation. And that's pretty approximate.

The type of RAM used in the computer. This indicator describes both the general level of "RAM" and the possibilities for replacing and upgrading it: different types of RAM are not compatible with each other.

Here are the types of memory that are relevant for modern PCs:

— DDR3. The third generation of RAM with the so-called double data transfer. Some time ago, this standard was the most popular in computer technology, but now it is increasingly losing ground to newer and more advanced standards, primarily DDR4. In compact computers, there is a "mobile", energy-saving version of this memory standard — LPDDR3.

— DDR3L. A modification of DDR3 memory that supports operation at a reduced voltage — 1.35 V instead of 1.5 V (Low Voltage — hence the index L). Lower voltage improves performance. These modules are compatible with classic DDR3 slots.

— DDR4. Further, after DDR3, the development of the DDR standard, released in 2014. It features both increased performance and increased volumes — the capacity of one bar can be from 2 to 128 GB. Thus, the maximum amount of RAM in most PCs is limited more by the capabilities of the motherboard than by the characteristics of existing brackets. DDR4 is very popular in modern computer technology, including desktop PCs.

The clock speed of the RAM that comes with the PC. This is one of the parameters that determine the capabilities of RAM: with the same amount and type of memory (see above), a higher clock frequency will mean faster performance. However such details are rarely required by an ordinary user, but they are important for enthusiasts and professionals.

Also note that this indicator can be used to determine the possibilities for upgrading the system: the motherboard will be able to work normally with brackets that have the same or lower clock frequency, but compatibility with faster memory should be specified separately.

The number of slots for RAM modules provided on the PC motherboard. In this case, we are talking about slots for removable strips; for a PC with built-in memory, this parameter is irrelevant.

The slots available on the "motherboard" can be occupied all, partially or not occupied at all (in models without RAM). Anyway, you should pay attention to their number if the initially installed amount of RAM does not suit you (or ceases to suit you over time), and you plan to upgrade the system. The smallest amount found in a PC with removable memory is 1 slot ; if it is busy, you will only have to change the bar when upgrading. More connectors for RAM are always paired, this is due to a number of technical nuances; most often this number is 2 or 4, but it can be large — up to 16 in powerful workstations.

Note that when planning an upgrade, you need to take into account not only the number of slots and type of memory (see above), but also the characteristics of the motherboard. All modern "motherboards" have restrictions on the maximum amount of RAM; as a result, for example, the presence of two DDR4 slots does not mean that two strips of maximum capacity can be installed in the system at once, 128 GB each.

The maximum amount of RAM that can be installed on a computer. It depends, in particular, on the type of memory modules used, as well as on the number of slots for them. Paying attention to this parameter makes sense, first of all, if the PC is bought with the expectation of upgrading RAM and the amount of actually installed memory in it is noticeably less than the maximum available

So the amount of maximum installed memory depends on the number of slots in the PC and can be from 16 GB(a modest PC) to 64 GB and above. The most popular on the market are PCs with a maximum installed 32 GB of memory.