[Guangwei Academy] Engineers help you understand the light knowledge of storage!
After the memory is installed, the total amount of memory available is only 14.9GB. Why? Will it be to buy memory with insufficient capacity?
When this happens, it usually takes up memory capacity at the bottom of the hardware. And this situation is particularly prone to appear on platforms that use core graphics. Compared to the independent graphics memory onboard the discrete graphics card, the core graphics card needs to share part of the system memory as display memory. In this case, just enter the BIOS to find the relevant settings.
As shown in the figure, in the North Bridge Settings/Display Settings column, “DVMT PRE-ALLOCATED” is set to 1024MB, which means that 1GB of memory is already allocated before entering the system. Memory usage.
You only need to re-allocate the memory size according to the system memory capacity. The above figure will correct the value to "64MB".
After re-entering the system, the total amount of memory is changed to 15.9GB, which means that about 1GB of memory that was previously occupied is re-run as system memory.
Question 2: What is the unit of measure for memory?
Memory is an important part of the von Neumann computer system. It also calculates and stores data in binary mode. The so-called binary is “0 and 1” for “off and on”. The computer judges a single data (1 bit) by "yes or no" at the time of calculation. This is the most basic unit of calculation. It is equivalent to the "atoms" in chemistry.
In ASCII code, "byte" consists of 2 8th power calculation units, a total of 256 arrangement methods. The single English letter we enter in the computer takes up one byte of space. A Chinese kanji takes up two bytes of space. "Byte" is the most basic storage unit (1Byte = 8bit).
The memory is used in the same unit of measure as the stored procedure.
1 KB = 1024 B; 1 MB = 1024 KB = 1024 × 1024 B. Where 1024=2^10.
1B (byte, byte) = 8 bit;
1KB (Kibibyte, kilobytes) = 1024B = 2^10 B;
1MB (Mebibyte, megabytes, megabytes, referred to as "mega") = 1024KB = 2^20 B;
1GB (Gigabyte, gigabyte, gigabyte, also known as "gigabit") = 1024MB = 2^30 B
However, in order to adapt to the measurement methods of people in daily life, the decimal process is still used in the storage process.
When the order of magnitude rises to TB, 1TB = 10^12, and its difference from the binary number begins to exponentially magnify.
The 1TB=1099511627776 in the binary differs from the 1TB in decimal by 99,511,627,776.
This is why there are always people who misunderstand the lack of disk capacity. However, the memory is only responsible for the temporary storage data, and the measurement is directly marked by the binary number, so there is no problem of capacity error.
Question 3: Why is memory called "inside", why not "outside"?
In the second question, we mentioned a name: Von Neumann. In his computer architecture theory, there are five major architectures: input devices, output devices, controllers, operators, and memories. In this architecture diagram, memory exists as a memory. Storage devices, such as hard disks and SSDs, that we usually recognize, are architecturally identical to mouse and keyboard and are input and output devices. It is simply inputting stored data to the computer and outputting the stored data.
A simple assumption is that when the motherboard, CPU and memory are working properly, we can see the most basic motherboard information screen and enter the BIOS. After throwing out the display device (to verify whether it can be turned on), these three constitute the most basic computing system, and memory is an indispensable part, but it exists only as a "cache", does not constitute The ultimate storage device, so it is customary to call it "memory".
Guangwei is a brand of Jiahe Jinwei Group, which is specialized in the storage industry for 16 years. The products occupy the mainstream in the storage market with excellent cost performance and stable performance, and launched the light strip product - β series last year. This school's full appearance is the GLOWAY beta series joy memory:
Well, this issue of memory light knowledge is over, welcome everyone to continue to pay attention to Guangwei's storage elementary school, to learn more about storage devices!