Lately we talk about RAM and SSDs, especially because of their brutal price increase in recent weeks and months. We must distinguish in this case that the memories used are similar or practically the same, but have slight differences between them, depending on the use we make of them. Specifically, we are talking about RAM modules and ROM modules, units to contain data, which have different in them, the most notable being that RAM does not store data and ROM memory does store data.
RAM
We start with Random Access Memory, better known as RAM. What these units do is constantly modify what is saved in these units. The amount of these memory depends on the budget of the user and for which a computer is intended, if it is for multimedia, with 4GB we are doing well, if it is for gaming at least 8GB are recommended and for Workstation, the normal thing is between 16GB and 32GB. These capacities depend on the programs used, since the heavier the processes, the more capacity we need to store all the data to be processed by the processor, without saturating it.
As we said, this type of memory is volatile, this means that when we turn off the equipment in question, this information is not saved, it is automatically erased. We must emphasize that there are basically two types of RAM memories:
- Dynamic RAM (DRAM): It is made up of capacitors, which require a controller chip to update the stored data every second, to avoid data loss. It is currently the most used in for desktop computers and mobile devices.
- Static RAM (SRAM): It differs from DRAM, in that these modules store data until there is a power failure, therefore a constant update of the data is not needed. The biggest disadvantage is that the density of the modules is lower and they are more expensive to manufacture, that is why it is used for special systems such as servers and other very specific spaces, where precision is required.
ROM memory
The other most common type of memory is Read-Only Memory or ROM, memories that are characterized by not being volatile, just the opposite that happens with RAM. This means that the information that we deposit in units with this type of memory, continue to save the data when the device stops having tension. In return, these are considerably slower than RAM. Initially, these were used in BIOS and other chips, because they only allowed the reading of stored data. Later it was achieved that these memories allowed the erasure and writing of data, generating USB memories, SD cards and SSD hard drives. There are also several times of ROM memories:
- ROM Mask: This type of memory receives a writing during the manufacturing process of the chip and cannot be modified later.
- Programmable Read-only Memory (PROM): Used mainly in household appliances and in which data is stored once the chip is manufactured, but that information cannot be modified.
- Erasable Programmable Read-only Memory (EPROM): Same as PROM, but in this case the data can be erased using high intensity ultraviolet light and new data stored on these chips.
- Electrically Erasable Programmable Read-only Memory (EEPROM): These memories are similar to the previous ones, but in this case they are erased by a specific voltage, which allows the data to be rewritten, in a limited way, since after an 'x' number of cycles, it degrades and stops working. Flash memories are made up of EEPROM memories and are used in smartphones, pen drives, SD cards, SSD hard drives and many other devices.
