Specifications of a CPU: part 2

Rest of the specifications of a CPU to be considered are:

• Instruction Set Size: Size of the instructions the processor can address simultaneously. It also defines the maximum amount of memory that the CPU can address. Currently, 32-bit and 64-bit.
• Memory Type: The standard and speed of RAM that the CPU is designed to address efficiently. If the RAM used in the system is other than the one specified by the CPU manufacturer, it may cause the system to lag.
• Max Memory Size: The maximum amount of physical memory that the CPU can support. If more RAM is installed than this, it may result in an unstable system.
• Number of Memory Channels: It specifies the number of RAM slots the CPU can work with efficiently. If the CPU is installed on a motherboard with more slots than this, it will cause the system to lag.
• PCI-E Support: Number of PCI Express slots supported and the PCI-E standard supported.
• Integrated Graphics: If the CPU has integrated graphics unit, then the graphics frequency is also to be considered.
• Socket Size: If you need to replace your processor, you need to be sure that the processor's socket size matches with the socket size of your existing motherboard.

Just keep in mind all of the above mentioned specifications while choosing a processor and you will have a super performance system.

Hardware caches

The first type of caches, the Hardware caches are usually memory chips that have been embedded within a device. The most common Hardware caches found in a computer system are:

• CPU cache: The L1,L2,L3 caches are used to speed-up data transfer between the processor and the main memory(i.e. RAM). The L1 and L2 caches are built right into the processor chip making them extremely fast. Whereas the newer L3 cache which also has higher capacity than L1 and L2, may be built into the motherboard as well.

• Optical drive cache: A small cache (typically 1-2 MB) is provided in all optical drives, whether CD or DVD or BD. This cache is present so that the disk burner has data available for burning, even if the CPU hits 100% utilization in some other process for a fraction of a second. The cache is also used to store data for fast access when a readable disk is first inserted into the drive.

• Hard-Disk cache: Hard-disks are the fastest permanent storage devices. They can virtually read and write data at the same time. For this purpose, a cache memory is provided in the hard drives that perform in a similar manner like the optical drive caches. The only difference is in their memory size. These may range from 8MB to 64MB.

Usually, the Hard-Disk and the Optical Disk caches are built into the hard-disk controller and the optical disk controller which are present on the hard-drives and the optical drives themselves.

Dynamic RAM: modules

DRAM packages are in turn often assembled into plug-in modules for easier handling. Some standard module types in order of increasing speeds are:

-DIP(Dual in-line Package) 16-pin (chip)

-SIPP(Single In-line Pin Package) (usually FPRAM)

-SIMM(Single In-line Memory Module) 30-pin (usually FPRAM)

-SIMM 72-pin (often EDO RAM)

-DIMM(Dual In-line Memory Module) 168-pin (SDRAM: Synchronous DRAM)

-DIMM 184-pin (DDR SDRAM: Double Data Rate SDRAM)

-RIMM(Rambus In-line Memory Module) 184-pin (RDRAM: Rambus DRAM)

-DIMM 240-pin (DDR2 SDRAM / DDR3 SDRAM)

Dynamic RAM: more info

Dynamic random-access memory (DRAM) is a type of random-access memory (RAM) that stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged; these two states are taken to represent the two values of a bit, conventionally called 0 and 1.

DRAM is volatile memory, since it loses its data quickly when power is removed. The transistors and capacitors used are extremely small; hundreds of billions can fit on a single memory chip.

Dynamic random access memory is produced as integrated circuits bonded and mounted into plastic packages with metal pins for connection to control signals and buses.

Today, these DRAM packages are in turn often assembled into plug-in modules that are installed into RAM sockets in the motherboard for easier handling.

DRAM is usually arranged in a square array of one capacitor and transistor per data bit storage cell. Typically, manufacturers specify that each row must have its storage cell capacitors refreshed every 64 ms or less. Refresh logic is provided in a DRAM controller which automates the periodic refresh, so no software or other hardware has to perform it. This makes the controller's logic circuit more complicated, but this drawback is outweighed by the fact that DRAM is much cheaper per storage cell and because each storage cell is very simple, DRAM has much greater capacity per geographic area than SRAM.

Motherboard: ports and sockets

This image shows only those interfaces (ports and sockets) that are important to our interest and point of view.

The rest of the small semiconductor parts of the motherboard are not of our interest, but for their designer.

In this post, only the names of all the interfaces have been mentioned.

Other than these interfaces, there are numerous chips and IC's for various functions as well.

They along with the functions of these interfaces would be described sometime later.

The components are so named:

A,B : PCI connector

C : CMOS battery

D : PCI-E (x1) connector

E : PCI-E (x16) connector

F : S/PDIF connector

G : Back-panel for I/O devices

H : 12V processor power (4-pin)

I : Rear chassis fan header (3-pin)

J : Processor socket

K : Processor fan header (4-pin)

L,M : RAM (channel A,B) sockets

N : Chassis intrusion header

O : Serial port header

P : Floppy Drive connector

Q : Main power connector (24-pin)

R : Parallel ATA (IDE) connector

S : Serial ATA (SATA) connectors

T : Front panel header

U : Alternate front panel power LED header

V : BIOS configuration jumper

W : Front USB headers

X : Speaker

Y : Front chassis fan header (3-pin)

Z : Front panel audio header