DRAM specification of mining machine
Publish: 2021-05-02 09:14:58
1. Future DDR4 memory will have two specifications. The transmission rate of DDR4 memory using single ended signaling signal has been confirmed to be 1.6-3.2gbps, while the transmission rate of DDR4 memory based on differential signal technology will reach 6.4gbps. Because it is impossible to implement two kinds of interfaces through one DRAM, there will be two kinds of procts based on traditional se signal and differential signal in DDR4 memory. Samsung Electronics announced on January 4, 2011 that it has completed the development of the first DDR4 DRAM memory mole in history, and has manufactured the first batch of samples with 30nm process. Up to now, the standard specification of DDR4 memory has not been finalized. Samsung this sample belongs to udimm type, the capacity is 2GB, the operating voltage is only 1.2V, the working frequency is 2133mhz, and with the new circuit architecture, the maximum can reach 3200mhz. In contrast, the standard frequency of DDR3 memory is up to 1600MHZ, the operating voltage is generally 1.5V, and the energy-saving version also has 1.35v. Only this point, DDR4 memory can save up to 40%. According to the previous plan, the maximum frequency of DDR4 memory may be as high as 4266mhz, and the voltage may drop to 1.1V or even 1.05v.
2. Answer your next 1 single 8 double 16 can capacity frequency best peer I platform requirements are relatively loose asymmetric al channel can be assembled remember to plug in the motherboard with the same color slot
3. Generally, flash memory can be divided into two specifications, one is NAND, the other is nor.
in short, NAND flash memory is like hard disk, which mainly stores data, also known as data flash. The chip capacity is large, and the current mainstream capacity has reached 2 GB; Nor memory is similar to DRAM, which mainly stores program code, also known as co de flash, so it can be read directly by microprocessor, but the chip capacity is low, and the mainstream capacity is 512 MB
in addition to the capacity difference between NAND and NOR flash memory, there is also a big difference in read-write speed. NAND chip can write and clear data much faster than nor chip, but nor chip can read data faster than NAND chip. NAND chips are mostly used in small memory cards to store data, while nor chips are mostly used in communication procts.
in short, NAND flash memory is like hard disk, which mainly stores data, also known as data flash. The chip capacity is large, and the current mainstream capacity has reached 2 GB; Nor memory is similar to DRAM, which mainly stores program code, also known as co de flash, so it can be read directly by microprocessor, but the chip capacity is low, and the mainstream capacity is 512 MB
in addition to the capacity difference between NAND and NOR flash memory, there is also a big difference in read-write speed. NAND chip can write and clear data much faster than nor chip, but nor chip can read data faster than NAND chip. NAND chips are mostly used in small memory cards to store data, while nor chips are mostly used in communication procts.
4. DDR is the double data rate. DDR is very similar to DRAM. Normal synchronous DRAM (now called SDR) is different from standard DRAM
the address command received by standard DRAM consists of two address words. In order to save the input pin, the scheme of multiplex transmission is adopted. The first address word is locked in DRAM chip by Ras. Following the RAS command, the column address gating (CAS) latch the second address word. Through Ras and CAS, the stored data can be read
synchronous dynamic random access memory (SDR DRAM) is composed of a standard DRAM and a clock. RAS, CAS and data availability are started at the rising edge of the clock pulse. According to the clock indication, the position of data and remaining instructions can be predicted. Therefore, the data latch gate can be accurately positioned. Due to the predictability of the effective data window, the memory can be divided into four areas for pre charging and pre acquisition of internal cells. Through the burst mode, continuous address acquisition can be carried out without repeated Ras gating. Continuous CAS gating can reproce data from the same source
the working principle of DDR memory and SDR memory is basically the same, except that DDR reads data at the rising and falling edges of clock pulse. The working frequency and data rate of the new generation DDR memory are 200MHz and 266MHz respectively, and the corresponding clock frequency is 100MHz and 133MHz
compared with DDR2 Memory, DDR3 memory is only an improvement in the specification, and there is no real new architecture of comprehensive upgrading. DDR3 has the same number of contact pins as DDR2. But the location of the gap is different, DDR3 frequency is above 800m, DDR2 frequency is below 800m
DDR4 memory has two specifications. The transmission rate of DDR4 memory using single ended signaling signal has been confirmed to be 1.6-3.2gbps, while the transmission rate of DDR4 memory based on differential signal technology will reach 6.4gbps. Because it is impossible to implement two kinds of interfaces through one DRAM, there will be two kinds of procts based on traditional se signal and differential signal in DDR4 memory
according to the introction of a number of relevant personnel in the semiconctor instry, DDR4 memory will coexist with single ended signaling (traditional se signal) and differential signaling (differential signal technology). Among them, Mr. Phil Hester of AMD also confirmed this. It is expected that these two standards will introce different chip procts, so in the DDR4 memory era, we will see two incompatible memory procts
the address command received by standard DRAM consists of two address words. In order to save the input pin, the scheme of multiplex transmission is adopted. The first address word is locked in DRAM chip by Ras. Following the RAS command, the column address gating (CAS) latch the second address word. Through Ras and CAS, the stored data can be read
synchronous dynamic random access memory (SDR DRAM) is composed of a standard DRAM and a clock. RAS, CAS and data availability are started at the rising edge of the clock pulse. According to the clock indication, the position of data and remaining instructions can be predicted. Therefore, the data latch gate can be accurately positioned. Due to the predictability of the effective data window, the memory can be divided into four areas for pre charging and pre acquisition of internal cells. Through the burst mode, continuous address acquisition can be carried out without repeated Ras gating. Continuous CAS gating can reproce data from the same source
the working principle of DDR memory and SDR memory is basically the same, except that DDR reads data at the rising and falling edges of clock pulse. The working frequency and data rate of the new generation DDR memory are 200MHz and 266MHz respectively, and the corresponding clock frequency is 100MHz and 133MHz
compared with DDR2 Memory, DDR3 memory is only an improvement in the specification, and there is no real new architecture of comprehensive upgrading. DDR3 has the same number of contact pins as DDR2. But the location of the gap is different, DDR3 frequency is above 800m, DDR2 frequency is below 800m
DDR4 memory has two specifications. The transmission rate of DDR4 memory using single ended signaling signal has been confirmed to be 1.6-3.2gbps, while the transmission rate of DDR4 memory based on differential signal technology will reach 6.4gbps. Because it is impossible to implement two kinds of interfaces through one DRAM, there will be two kinds of procts based on traditional se signal and differential signal in DDR4 memory
according to the introction of a number of relevant personnel in the semiconctor instry, DDR4 memory will coexist with single ended signaling (traditional se signal) and differential signaling (differential signal technology). Among them, Mr. Phil Hester of AMD also confirmed this. It is expected that these two standards will introce different chip procts, so in the DDR4 memory era, we will see two incompatible memory procts
5. 1 DDR2 with memory is the actual working frequency of identification frequency / 4! DDR memory transmits data twice on the top and bottom edge of the clock signal, so it is equivalent to: working frequency * 2, DDR2 Memory works through the internal chip of the memory, and the working frequency is twice that of the external bus, so the internal actual working frequency of the memory particle is 333, and the external working frequency (bus frequency, external frequency) is 166, which is equivalent to 667mhz< br />2 The ratio of FSB: DRAM should not be 1:1, but should be adjusted to the actual working frequency of memory! Because this memory will not be used down frequency (such as DDR2 800)! This option is used for overclocking memory! That is to say, high frequency memory can be used to identify (rated) frequency< br />3 If I insert another 1G memory to form an unequal al channel, the memory frequency will not be doubled and the bandwidth will be doubled
the working frequency of general memory is the external frequency of CPU! It's just that the algorithm is different! Their actual working frequency: DDR1 band is divided by 2, the second generation is divided by 4
for details, you can add QQ to ask: 378343412
the working frequency of general memory is the external frequency of CPU! It's just that the algorithm is different! Their actual working frequency: DDR1 band is divided by 2, the second generation is divided by 4
for details, you can add QQ to ask: 378343412
6. IC: (integrated circuit) integrated circuit, which integrates several transistors on a single silicon chip by a special process to realize functions that can only be realized by several discrete components< EEPROM: (electrically erasable programmable read-only memory), which I translate as EEPROM, and some books are also translated as EEPROM. The feature of EEPROM is that it can store data after power down, but the disadvantage is that the storage speed is slow, and the early EEPROM needs high-voltage operation. The current EEPROM is generally integrated with a voltage pump, and the reading and writing speed is less than 250 nanoseconds, so it is very convenient to use< Flash is a kind of EEPROM, but it has fast storage speed and excellent manufacturing technology. The core component of U disk is flash< SDRAM (synchronous dynamic random access memory) is a kind of synchronous dynamic random access memory. It is described in the network as follows: "synchronization means that memory needs a synchronous clock to work, and internal command sending and data transmission are based on it; Dynamic means that the storage array needs constant refresh to ensure that the data is not lost; Random means that the data is not stored in a linear order, but is read and written by freely specifying the address
"
DRAM: (dynamic random access memory), dynamic random access memory
I don't know how your analog and digital electronics are, and have you ever actually touched electronic components. You ask these questions as if you know nothing about electronics, so I can't further explain SDRAM and DRAM, as well as their differences, advantages and disadvantages. By the way, do you sell electronic components?
"
DRAM: (dynamic random access memory), dynamic random access memory
I don't know how your analog and digital electronics are, and have you ever actually touched electronic components. You ask these questions as if you know nothing about electronics, so I can't further explain SDRAM and DRAM, as well as their differences, advantages and disadvantages. By the way, do you sell electronic components?
7. Hot summer, constant passion, bright 64 bit storm in the past summer really prosperous. Low price, strong overclocking capability, support for sse3 and x86-64 instruction set, all these are all telling the endless charm of 754 pin sempron2500 + processor. Today, the author will talk about the process and method of CPU overclocking with this classic 64 bit processor proct, hoping to be helpful for your purchase
overclocking can be roughly divided into two categories: one is for overclocking, only for better performance; Second: overclocking while using, not only to experience higher performance, but also to ensure enough stability. Before overclocking, you must first establish your own positioning, so that you can focus on your goal and get twice the result with half the effort. Moreover, there are differences in BIOS settings between the two: the former needs to turn off the unused floppy drive, optical drive, IDE, s-ata, on-board sound card, on-board network card, 1394, USB, parallel port, serial port, infrared port, etc, In order to minimize the interference caused by frequency mismatch and other factors; The latter obviously can't be set in this way. It should ensure the function perfection while ensuring the overclocking. Therefore, it is only necessary to simply modify the overclocking option in BIOS, otherwise it is equivalent to the failure of overclocking (for example, the process of overclocking may cause the sound card and network card can't be used, etc.)
over frequency principle:
CPU actual running frequency = external frequency × Frequency doubling, so we only need to change any one of the external frequency and frequency doubling to achieve overclocking. Of course, we can also combine the two. Because it is relatively simple to adjust the external frequency separately, it is recommended for general users; For advanced players, it can also cooperate with frequency doubling to achieve better overclocking effect, but the final performance improvement is not necessarily proportional to the improvement of external frequency (such as 330mhz) × 7 is better than 350 MHz × 6
precautions for overclocking:
firstly, the ambient temperature affects the overclocking, so it is necessary to choose a high-quality radiator; Secondly, graphics card, memory, PCI bus may become the bottleneck of restricting the CPU to play, so asynchronous mode should be adopted to make it work at standard frequency; Finally, increasing the working voltage will help to further improve the overclocking frequency, but remind players to adjust step by step, do not act too hastily, too high voltage will rece the overclocking performance, but also increase the risk of burning CPU
before overclocking, let's first understand the specifications of AMD Sempron 2500 + processor: main frequency 1.4GHz, frequency doubling 7x, core E6 (lower energy consumption and calorific value), 90nm SOI process, 1.4V core voltage, maximum temperature 69 ℃ °， Power consumption 62W, 128K L1 cache, 256K L2 cache, support sse3 and 6x86-64 instructions, interface type socket 754
this Onda thermal storm nf4x motherboard provides up to 450MHz external frequency regulation. Due to the external frequency and HT frequency (FSB) × If the HT frequency of nf4-4x chipset is 1000MHz, that is to say, when the external frequency reaches 250MHz, the HT frequency is adjusted to 4 × It is the most reliable. By analogy, it should not exceed the HT frequency supported by the chipset as far as possible. Reasonable adjustment of HT frequency doubling is helpful to advance to high external frequency. For example, when we raise the external frequency to 330mhz, we need to rece the HT bus ratio to 3x, so that the HT bus frequency is within 1000MHz. In addition, in order to make the overclocking stable, we can also adjust the voltage of the chipset appropriately
another very important factor is the memory. The default frequency of DDR400 memory is 200MHz. When we overclock the front-end bus, the memory frequency will also increase to more than 200MHz. Due to the non-standard frequency, the memory particles are overloaded, and the system is prone to collapse. Here we propose such a solution, that is to customize the memory frequency below 200MHz before overclocking. In this way, even if the memory frequency rises after overclocking, it will not exceed the upper limit of 200MHz memory frequency. For example, when we increase the external frequency to 330mhz, if the memory is synchronized, the memory will work under ddr660, which is difficult to achieve. Since we are using ddr500 memory, we set the memory ratio of 1:0.8 here. When the external frequency is 320mhz, the memory works at 256mhz
as for the adjustment of CPU voltage, we don't need to increase the voltage value at the beginning, whether it is pressurized or whether it is sufficient after overclocking. If you are not familiar with the hardware, the general users still recommend to use the default voltage. We recommend not more than 1.6V in air cooling and not more than 1.7V in water cooling
at present, most flash dragon overclocking motherboards provide 3.0V DDR memory voltage regulation. In the overclocking state, the DDR frequency soars with the rise of the front-end bus, which is very likely to cause instability. At this time, if the DDR voltage is properly increased, it will help to stabilize the system
finally, let's talk about the details of other aspects: try to keep the value of "PCI Express clock" option at 100; Shut down all ports that are not used in daily life; When the CPU is over frequency, it's better to adjust by megabyte to find the best over frequency point; When the CPU external frequency has been unable to improve, we might as well rece the multiplier value appropriately, which will help to further improve the external frequency<
summary:
this paper aims to show players how to achieve CPU overclocking. The overclocking process of AMD Sempron 2500 + and Onda thermal storm nf4x motherboard platform is not suitable for all players. It is suggested that you refer to our overclocking steps for relevant settings according to your own platform characteristics.
overclocking can be roughly divided into two categories: one is for overclocking, only for better performance; Second: overclocking while using, not only to experience higher performance, but also to ensure enough stability. Before overclocking, you must first establish your own positioning, so that you can focus on your goal and get twice the result with half the effort. Moreover, there are differences in BIOS settings between the two: the former needs to turn off the unused floppy drive, optical drive, IDE, s-ata, on-board sound card, on-board network card, 1394, USB, parallel port, serial port, infrared port, etc, In order to minimize the interference caused by frequency mismatch and other factors; The latter obviously can't be set in this way. It should ensure the function perfection while ensuring the overclocking. Therefore, it is only necessary to simply modify the overclocking option in BIOS, otherwise it is equivalent to the failure of overclocking (for example, the process of overclocking may cause the sound card and network card can't be used, etc.)
over frequency principle:
CPU actual running frequency = external frequency × Frequency doubling, so we only need to change any one of the external frequency and frequency doubling to achieve overclocking. Of course, we can also combine the two. Because it is relatively simple to adjust the external frequency separately, it is recommended for general users; For advanced players, it can also cooperate with frequency doubling to achieve better overclocking effect, but the final performance improvement is not necessarily proportional to the improvement of external frequency (such as 330mhz) × 7 is better than 350 MHz × 6
precautions for overclocking:
firstly, the ambient temperature affects the overclocking, so it is necessary to choose a high-quality radiator; Secondly, graphics card, memory, PCI bus may become the bottleneck of restricting the CPU to play, so asynchronous mode should be adopted to make it work at standard frequency; Finally, increasing the working voltage will help to further improve the overclocking frequency, but remind players to adjust step by step, do not act too hastily, too high voltage will rece the overclocking performance, but also increase the risk of burning CPU
before overclocking, let's first understand the specifications of AMD Sempron 2500 + processor: main frequency 1.4GHz, frequency doubling 7x, core E6 (lower energy consumption and calorific value), 90nm SOI process, 1.4V core voltage, maximum temperature 69 ℃ °， Power consumption 62W, 128K L1 cache, 256K L2 cache, support sse3 and 6x86-64 instructions, interface type socket 754
this Onda thermal storm nf4x motherboard provides up to 450MHz external frequency regulation. Due to the external frequency and HT frequency (FSB) × If the HT frequency of nf4-4x chipset is 1000MHz, that is to say, when the external frequency reaches 250MHz, the HT frequency is adjusted to 4 × It is the most reliable. By analogy, it should not exceed the HT frequency supported by the chipset as far as possible. Reasonable adjustment of HT frequency doubling is helpful to advance to high external frequency. For example, when we raise the external frequency to 330mhz, we need to rece the HT bus ratio to 3x, so that the HT bus frequency is within 1000MHz. In addition, in order to make the overclocking stable, we can also adjust the voltage of the chipset appropriately
another very important factor is the memory. The default frequency of DDR400 memory is 200MHz. When we overclock the front-end bus, the memory frequency will also increase to more than 200MHz. Due to the non-standard frequency, the memory particles are overloaded, and the system is prone to collapse. Here we propose such a solution, that is to customize the memory frequency below 200MHz before overclocking. In this way, even if the memory frequency rises after overclocking, it will not exceed the upper limit of 200MHz memory frequency. For example, when we increase the external frequency to 330mhz, if the memory is synchronized, the memory will work under ddr660, which is difficult to achieve. Since we are using ddr500 memory, we set the memory ratio of 1:0.8 here. When the external frequency is 320mhz, the memory works at 256mhz
as for the adjustment of CPU voltage, we don't need to increase the voltage value at the beginning, whether it is pressurized or whether it is sufficient after overclocking. If you are not familiar with the hardware, the general users still recommend to use the default voltage. We recommend not more than 1.6V in air cooling and not more than 1.7V in water cooling
at present, most flash dragon overclocking motherboards provide 3.0V DDR memory voltage regulation. In the overclocking state, the DDR frequency soars with the rise of the front-end bus, which is very likely to cause instability. At this time, if the DDR voltage is properly increased, it will help to stabilize the system
finally, let's talk about the details of other aspects: try to keep the value of "PCI Express clock" option at 100; Shut down all ports that are not used in daily life; When the CPU is over frequency, it's better to adjust by megabyte to find the best over frequency point; When the CPU external frequency has been unable to improve, we might as well rece the multiplier value appropriately, which will help to further improve the external frequency<
summary:
this paper aims to show players how to achieve CPU overclocking. The overclocking process of AMD Sempron 2500 + and Onda thermal storm nf4x motherboard platform is not suitable for all players. It is suggested that you refer to our overclocking steps for relevant settings according to your own platform characteristics.
8. SRAM is the abbreviation of static RAM. It is a kind of memory with static access function. It can save the data stored in it without refreshing the circuit. Unlike DRAM memory, which needs a refresh circuit, it needs to refresh and charge DRAM every other time, otherwise the internal data will disappear, so SRAM has high performance. But SRAM also has its disadvantages, that is, its integration is low. DRAM memory with the same capacity can be designed as a small volume, but SRAM needs a large volume, So on the motherboard SRAM memory to occupy part of the area, on the motherboard which is SRAM? One is the cache between CPU and main memory, which has two specifications: one is the cache memory fixed on the motherboard; the other is the cache memory fixed on the motherboard; The other is the cache for expanding the cost (Cache on a stick) inserted in the card slot. In addition, in the circuit of CMOS chip 1468l8, there is a smaller 128 byte SRAM inside to store the configuration data we set. In addition, in order to speed up the internal data transmission of CPU, since 80486 CPU, cache has also been designed inside CPU. Therefore, in Pentium CPU, there are so-called L1 cache (Level 1 cache) and l2cache (Level 2 cache). Generally, L1 cache is built inside CPU and L2 cache is designed outside CPU, However, Pentium Pro designs L1 and L2 caches in the CPU at the same time, so the volume of Pentium Pro is large. The latest Pentium II moves L2 cache to a black box outside the CPU core. SRAM is obviously fast and does not need to be refreshed, but it also has another disadvantage, that is, it is expensive and bulky, so it can not be used as a large amount of main memory on the motherboard. Now its characteristics are summarized as follows: advantages, fast speed, no need to cooperate with the memory refresh circuit, can improve the overall efficiency. Disadvantages: low integration, high power consumption, large volume of the same capacity, and high price. A small amount is used in key systems to improve efficiency. System used by SRAM: cache between CPU and main memory. The internal L1 / L2 or external L2 cache of CPU. The cost cache for external expansion of CPU. CMOS 146818 chip (RT & CMOS SRAM).
9. DRAM (dynamic random access memory) is the most common system memory. DRAM can only keep data for a short time. In order to keep data, DRAM uses capacitive storage, so it must refresh every other time. If the storage unit is not refreshed, the stored information will be lost
flash is a standard for interactive vector graphics and web animation developed by Macromedia company. Web designers use flash to create beautiful and size changeable navigation interface and other strange effects. SRAM is the abbreviation of static RAM. It is a kind of memory with static access function, which can save its internal data without refreshing the circuit. Unlike DRAM memory, which needs a refresh circuit, it needs to refresh and charge DRAM every other time, otherwise the internal data will disappear, so SRAM has high performance. But SRAM also has its disadvantages, that is, its integration is low. DRAM memory with the same capacity can be designed as a small volume, but SRAM needs a large volume, So on the motherboard SRAM memory to occupy part of the area, on the motherboard which is SRAM
one is the cache between CPU and main memory, which has two specifications: one is the cache memory fixed on the motherboard; the other is the cache memory fixed on the motherboard; The other is the cache for expanding the cost (Cache on a stick) inserted in the card slot. In addition, in the circuit of CMOS chip 1468l8, there is a smaller 128 byte SRAM inside to store the configuration data we set. In addition, in order to speed up the internal data transmission of CPU, since 80486 CPU, cache has also been designed inside CPU. Therefore, in Pentium CPU, there are so-called L1 cache (Level 1 cache) and l2cache (Level 2 cache). Generally, L1 cache is built inside CPU and L2 cache is designed outside CPU, However, Pentium Pro designs L1 and L2 caches in the CPU at the same time, so the volume of Pentium Pro is large. The latest Pentium II moves L2 cache to a black box outside the CPU core. SRAM is obviously fast and does not need to be refreshed, but it also has another disadvantage, that is, it is expensive and bulky, so it can not be used as a large amount of main memory on the motherboard. Now its characteristics are summarized as follows:
advantages, fast speed, no need to cooperate with the memory refresh circuit, can improve the overall efficiency
disadvantages: low integration, high power consumption, large volume of the same capacity, and high price. A small amount is used in key systems to improve efficiency
the utram you said should be UTRAN
UTRAN (universal terrestrial radio access) global terrestrial wireless access
UMTS structure includes a universal wireless access network, UMTS wireless access network (uran). Uran can be implemented in many different ways. According to different conditions and environments, we can use the existing access network to achieve by evolution, or we can use advanced technology to achieve a new access network
UTRAN is a new access network and the most important access mode of UMTS, which has the widest application range. The basic principle of defining UTRAN structure is that signaling network and data transmission network are logically separated; The function of UTRAN and CN will be completely separated from the transmission function; The addressing mode used by UTRAN and CN will have nothing to do with the addressing mode of transmission function; The processing of macro diversity (FDD mode) is completely in UTRAN; The mobility of RRC connection is completely controlled by UTRAN; When defining UTRAN interface, there should be as few options as possible through the function division of the interface; The logical model of the entity that should be controlled based on this interface
the control plane of the transmission network is the function plane of the interface protocol structure used for transmission bearer management. The signaling protocol used in the control plane of the transmission network is related to the transport layer technology below
1) structure of UTRAN
UTRAN consists of a group of wireless network subsystems (RNs) connected to the core network through iu interface. An RNs consists of a radio network controller (RNC) and one or more Node Bs. Node B is connected to RNC through Iub interface. Node B can support FDD mode, TDD mode or al mode. RNC includes the merge / split function to support macro diversity between different node B, and makes decisions on the handoff that needs signaling connection with UE. The B node supporting FDD mode can include an optional merge / split function supporting macro diversity in node B
in UTRAN, RNCs in wireless network subsystem can be connected through IUR. IU and IUR interfaces are logical interfaces. IUR can be transmitted through physical direct connection between RNCs or through any suitable transmission network
RNs is responsible for the resources required by the cells within its scope. For each connection between user equipment and UTRAN, there is an RNs serving the RNs. If necessary, drift RNs can provide wireless resources to support service RNs
2) the function of UTRAN
system access is a way for UMTS users to connect to UMTS in order to use UMTS services. The initiator of user system access can be mobile terminal or network terminal
If graphics memory is like video memory in a computer
flash is a standard for interactive vector graphics and web animation developed by Macromedia company. Web designers use flash to create beautiful and size changeable navigation interface and other strange effects. SRAM is the abbreviation of static RAM. It is a kind of memory with static access function, which can save its internal data without refreshing the circuit. Unlike DRAM memory, which needs a refresh circuit, it needs to refresh and charge DRAM every other time, otherwise the internal data will disappear, so SRAM has high performance. But SRAM also has its disadvantages, that is, its integration is low. DRAM memory with the same capacity can be designed as a small volume, but SRAM needs a large volume, So on the motherboard SRAM memory to occupy part of the area, on the motherboard which is SRAM
one is the cache between CPU and main memory, which has two specifications: one is the cache memory fixed on the motherboard; the other is the cache memory fixed on the motherboard; The other is the cache for expanding the cost (Cache on a stick) inserted in the card slot. In addition, in the circuit of CMOS chip 1468l8, there is a smaller 128 byte SRAM inside to store the configuration data we set. In addition, in order to speed up the internal data transmission of CPU, since 80486 CPU, cache has also been designed inside CPU. Therefore, in Pentium CPU, there are so-called L1 cache (Level 1 cache) and l2cache (Level 2 cache). Generally, L1 cache is built inside CPU and L2 cache is designed outside CPU, However, Pentium Pro designs L1 and L2 caches in the CPU at the same time, so the volume of Pentium Pro is large. The latest Pentium II moves L2 cache to a black box outside the CPU core. SRAM is obviously fast and does not need to be refreshed, but it also has another disadvantage, that is, it is expensive and bulky, so it can not be used as a large amount of main memory on the motherboard. Now its characteristics are summarized as follows:
advantages, fast speed, no need to cooperate with the memory refresh circuit, can improve the overall efficiency
disadvantages: low integration, high power consumption, large volume of the same capacity, and high price. A small amount is used in key systems to improve efficiency
the utram you said should be UTRAN
UTRAN (universal terrestrial radio access) global terrestrial wireless access
UMTS structure includes a universal wireless access network, UMTS wireless access network (uran). Uran can be implemented in many different ways. According to different conditions and environments, we can use the existing access network to achieve by evolution, or we can use advanced technology to achieve a new access network
UTRAN is a new access network and the most important access mode of UMTS, which has the widest application range. The basic principle of defining UTRAN structure is that signaling network and data transmission network are logically separated; The function of UTRAN and CN will be completely separated from the transmission function; The addressing mode used by UTRAN and CN will have nothing to do with the addressing mode of transmission function; The processing of macro diversity (FDD mode) is completely in UTRAN; The mobility of RRC connection is completely controlled by UTRAN; When defining UTRAN interface, there should be as few options as possible through the function division of the interface; The logical model of the entity that should be controlled based on this interface
the control plane of the transmission network is the function plane of the interface protocol structure used for transmission bearer management. The signaling protocol used in the control plane of the transmission network is related to the transport layer technology below
1) structure of UTRAN
UTRAN consists of a group of wireless network subsystems (RNs) connected to the core network through iu interface. An RNs consists of a radio network controller (RNC) and one or more Node Bs. Node B is connected to RNC through Iub interface. Node B can support FDD mode, TDD mode or al mode. RNC includes the merge / split function to support macro diversity between different node B, and makes decisions on the handoff that needs signaling connection with UE. The B node supporting FDD mode can include an optional merge / split function supporting macro diversity in node B
in UTRAN, RNCs in wireless network subsystem can be connected through IUR. IU and IUR interfaces are logical interfaces. IUR can be transmitted through physical direct connection between RNCs or through any suitable transmission network
RNs is responsible for the resources required by the cells within its scope. For each connection between user equipment and UTRAN, there is an RNs serving the RNs. If necessary, drift RNs can provide wireless resources to support service RNs
2) the function of UTRAN
system access is a way for UMTS users to connect to UMTS in order to use UMTS services. The initiator of user system access can be mobile terminal or network terminal
If graphics memory is like video memory in a computer
10. Yes, the DDR2 800 memory frequency is 400MHz.
it can't be said to be an absolute average. If the three frequencies are the same, it is the average naturally.
if the three frequencies are different, for example, two are 800 and one is 667, then the lowest frequency 333 will be displayed, because if the three memories with different frequencies are used together, the system will operate according to the lowest memory frequency, That is to say, the other two 800's memory will be reced to 667
it can't be said to be an absolute average. If the three frequencies are the same, it is the average naturally.
if the three frequencies are different, for example, two are 800 and one is 667, then the lowest frequency 333 will be displayed, because if the three memories with different frequencies are used together, the system will operate according to the lowest memory frequency, That is to say, the other two 800's memory will be reced to 667
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