- The parameter “Fast Command” (Optimization Mode or Top Performance) enables to set the amount of delays during exchange of data or commands between the processor and memory. This parameter may have the following values: Ultra, Fast and Normal (Turbo2, Turbo1 and Normal or Enabled and Disabled). But if the memory modules are not very qualitative, the speeding of information exchange may cause failures in operation of memory.
- The parameter “CPU Fast String” specifies the possibility of direct request of processor to operating memory. This parameter may have the following values: Enabled and Disabled.
- The parameter “SDRAM1T Command” (DDR Command Rate or DDR 1T/2T Item) enables to set the amount of delays during the exchange of commands between chipset and memory. This parameter has values “2T” or “Disabled” by default. If to set the values “1T” (Enabled), you can increase the effectiveness of interaction between memory and chipset that have a positive impact on the whole system.
- The parameter “Chipset NA# Asserted” enables to specify the possibility of using the conveyor effect when the chipset informs about readiness of a new memory address before all the data in the current cycle will be processed. This parameter has got two values: Enabled and Disabled.
- The parameter “CPU DRAM Back-Back Transaction” enables to switch on the possibility of fast writing of data packets transmitted by a processor in operating memory. This parameter has got two values: Enabled and Disabled. If you enable the fast and direct interaction between memory and processor, you will increase the speed of system operation.
Except delays and BIOS parameters that set immediate values of reading and writing into the memory, there are also several parameters enabling to configure memory for its optimal interaction with other devices. Here are some of them:
- The parameter “SDRAM Frequency” (DRAM Clock) enables to set the bus frequency on which the memory operates, different from the frequency on which the processor operates. This parameter may have several values: SPD – the frequency is specified by plants wired in SPD-block of memory module; HCLK – the frequency of memory bus is consistent with the frequency of system bus; HCLK+33 (or HCLK-33) – the frequency of memory bus is 33 MHz higher (or lower) than the frequency of system bus. Sometimes the immediate indication of frequencies may be used as the values, for example 66 MHz, 100 MHz, 133 MHz, 200 MHz, 266 MHz, 333 MHz, 400 MHz.
- The parameter “Bank Interleave” (SDRAM Bank Interleave) sets an interleave mode of memory banks. This parameter enables to use the conveyor effect: while one logic bank undergoes a cycle of the contest update, the other one is in active status and undergoes the storage cycle. Such process improves the effectiveness of memory functioning. This parameter may have three values: Disabled, 2 Bank (2-Way) or 4 Bank (4-Way). If your system uses the modules of 16 MB, then this parameter should have the value “Disabled”. Selection of “2 Bank” (2-Way) or 4 Bank (4-Way) depends on the amount of memory: the value “2 Bank” (2-Way) is used for the memory of 32 and 64 MB, and “4 Bank” (4-Way) is used for modules of larger amount or when your system uses several memory modules.
- The parameter “CAS# Latency” (CAS# Latency Clocks) describes a very important feature of memory module – a minimal number of cycles from the moment of data request by CAS to their occurrence and stable reading from the outputs of memory module. This parameter may have 2 values: 2T and 3T (or 2 Clks and 3 Clks). The higher value is always set by default for this parameter. Decreasing the value allows speeding up the process of data reading from memory and, accordingly, increasing the system performance: setting two-tact value speeds the system up to 1-2% compared with three tacts. But not all memory micro chips will operate steadily after changing the value of this parameter. So if you buy the memory module, pay attention not only to memory specification (PC100 or PC133) but to the time of delay CAS Latency (CL). The memory with CL = 2 has maximum performance and operates steadily on frequencies of 100 – 133 MHz.
- The parameter “Row Precharge Time” (SDRAM RAS Precharge Time) enables to specify the number of clocks before the cycle of memory regeneration. This parameter has got two values: 2T and 3T (or Fast and Slow). The lower value (Fast) allows increasing the performance of memory while the higher value (Slow) increases the stable operation of your computer.
- The parameter “RAS# Pulse Width” specifies the number of clocks during which the signal RAS is active. This parameter may have various values: from 3 clocks (3T) to 7 (7T). Decreasing the time of RAS activity increases the system performance but some memory modules may have failures.
- The parameter “DRAM RAS Precharge Time” identifies the time (in clocks) which is required to amass the charge before the beginning of regeneration cycle of the neighboring memory rows. This parameter may have such values as 3T or 4T, Fast or Slow, or specific values in milliseconds: 7.8 ms, 15.6 ms, 32.2 ms and 64.4 ms. In contrast to the other parameters, this delay needs to be increased, but a large increase in time of this delay may cause destabilization in memory operation.
- The parameter “MA Wait State” enables to set or delete an additional waiting clock before reading memory. This parameter may have values Fast or Slow. For EDO-memory, the value “Slow” adds one more waiting clock to the existing clock.
- The parameter “Read Around Write” enables to use the buffer of data storage. This buffer stores the data while “Read Data” operation is performed and writes these data in memory after the bus is exempted. This parameter may have values “Enabled” and “Disabled”. Using such buffer allows significantly optimizing the operation of memory.
- The parameter “DRAM Idler Timer” enables to set a timer of passive memory status, defining the time during which all opened memory pages will be closed when a processor enters the standby mode. This parameter may have the following values: 0T, 2T, 4T, 8T, 10T, 12T, 16T and 32T. The values 2T or 4T will be quite sufficient for stable operation of your memory.
Before or during any operation of data reading-writing, there are various delays that are necessary for the stabilization of operation. In some cases, decreasing of delays allows speeding up the operation of memory, but remember, if you computer becomes unstable or “hangs’, it is better to return to default values.
- The parameter “DRAM R/W Leadoff Timing” defines the number of cycles spent by memory while preparing an operation of data reading-writing. This parameter may have values 7/8 or 7/5: the first number indicates the amount of cycles spent while reading and the second – while writing.
- The parameter “Speculative Leadoff” allows using the mode of anticipating signaling of data reading. This parameter has got two values: Disable or Enable. If you turn this parameter on, you may save several cycles spent by default on identification of the address of the required cell.
- The parameter “Fast RAS-to-CAS Delay” (RAS# to CAS# Address Delay, RAS to CAS Delay Time, DRAM RAS to CAS Delay, FPM/EDO RAS-to-CAS Delay, SDRAM RAS# to CAS# Delay) defines the time of delay between control signals (strobes) of the calls to the columns and rows. This delay is intended for identification of the row address of memory cell which is determined by RAS (Row Address Strobe), and the columns address which is determined by CAS (Column Address Strobe). Different versions of BIOS offer various values to set this delay: Fast and Slow, Enabled or Disabled, 2Clks or 3Clks (clocks). In some cases there may be a set of values: 0T (instead of Clks), 1T, 2T, 3T.
In some versions of BIOS you can find the parameters enabling to set the circuit of memory functioning. As a rule, to control reading-writing, you may use the parameters “DRAM Read Timing and DRAM Write Timing (DRAM Read Burst (EDO/FP) and DRAM Write Burst Timing). There are different variants of permissible circuits of memory access: x333 or x444 – for FPM DRAM; x333 – for EDO DRAM. If you set the value which describes “shorter” circuit, you may achieve some productivity improvement.
You can also find the configuration parameters of the circuit of memory functioning in more modern types of memory – SDRAM or BEDO DRAM. The circuit of memory functioning is very simple for these types: 5111 – 1111 – …, i.e. all required addresses are specified when reading the first bit. You may use the values x111 or x222 for parameters of these memory types.
To setup memory means to select the configuration of values with which all delays of preservation and retrieval of information will be minimal. These delays derive from waiting-time of read and write permissions in a particular location, the time of transition to a particular cell or a group of cells with the required information and other.
Let’s review the main parameters enabling to speed up the speed of memory.
In simple terms, memory is a table which consists of rows and columns. There are cells on their crossing, each of which stores the information unit – a logical value 0 or 1. All the data in memory are converted into binary numbers, i.e. all data in memory are sets of zeros and ones in several neighboring cells.
To read the content of one of memory cell, five cycles of memory bus are necessary:
- specify the line address;
- the control signal (strobe) confirms the receipt of address;
- the main signal is sent on the column address;
- the control signal is sent on the column address;
- read data.
DIMM and DDR
Nowadays the most widely used memory modules are DIMM and DDR (of SDRAM and SDRAM II). In comparison with SIMM-modules, their advantages are increased productivity from synchronization of signals and a special micro chip SPD that contains information about the configuration of this memory module. Such information is not optimal – the manufacturers provide values in SPD-blocks of memory modules enabling to operate on the motherboards of all types that support these modules. This does not guarantee the maximum performance. It should be noted that there are some cheap unnamed memory modules without SPD-blocks which cannot be defined as devices of appropriate use by some motherboards.
To configure memory manually, switch off the device which automatically sets all parameters. To do this, use the parameter “SDRAM Configuration”. Select the following fixed values: 7 ns (143 MHz), 8 ns (125 MHz) and 10 ns (100 MHz). When using fixed values, the maximum performance is equal to 7 ns (143 MHz).
For the purpose of marking Random Access Memory (RAM), most users use a simple and capacious name – memory.
The main parameters of BIOS enabling to get the additional increase of the computer’s capacity in a cost-effective manner are various delays, specific operating modes, operation mechanisms and others.
Almost all parameters enabling to control operating memory are located in a section “Advanced Chipset Setup” (Chipset Features Setup). Depending on the type and version of BIOS, the parameters of memory setting may be gathered in a separate subsection which may be called “DRAM Timing Control”. BIOS automatically sets all values for memory parameters by default, depending on the types of set memory modules.
FPM and EDO RAM placed on SIMM are outdated ones. But a lot of organizations still use the computers equipped with this type of memory. Nowadays SIMM-modules are rather scarce – they may only be used as their production was stopped about eight years ago. That’s why this kind of memory needs to be optimized.
The parameter “Auto Configuration” (DRAM Auto Configuration, Auto Configure EDO DRAM Tim) controls switching between automatic and manual setting of memory values. This parameter allows indicating one of fixed values of duration terms of data access: 60 ns or 70 ns. To optimize memory manually, set the values “User” or “Disable” for this parameter.
The values “60 ns” or “70 ns” indicate the use of presets which ensure stable operation of memory on the basis of set duration of access cycle. It is clear that soma part of the highest possible productivity is lost.
If the processor temperature increases, it noticeably loses its productivity. After exceeding of some critical temperature, a processor “burns” – this is the main cause of its failure.
The processor overheating is the main cause impeding its overclocking and normal productivity. If you buy a new processor or computer, always ensure if there is a good fan. You should not skimp on this.
A common fan consists of a radiator extracting the heat and a propeller moving the hot air. So, the better radiator and the more ribs it has, the better heat is transferring from the processor. And the faster a propeller rotates, the better this heat is extracted. Nowadays two-propeller systems are widely spread, but such fans are very noisy and you may buy them only if your system unit will be kept rather far from users. You can also find the cooling water systems but they are rather expensive.
No air layers should be between the processor and fan – a good thermal insulator significantly influences the heat transfer from a processor. To extract the air and to improve the heat-exchange, use special silicone thermal grease. Spread it with thin layer between the fan radiator and a processor.
A size of your system unit, the power of a fan and additional sources of ventilation also significantly influence the processor’s temperature.