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.

Specifications of a CPU: part 1

The processors also have performance specifications that a buyer must know accurately before purchasing the product. As in the case of Hard Disks, better specs of the CPU will make the system perform faster. This topic has been divided into two posts to make them short and readable. The specification categories are:

• Number of Cores: Cores are the physical sub-units of a processor that can process individually. Each core has its own computing units, CPU caches and lookaside buffer. More the number of cores, more instructions can be executed independently at the same time.
• Number of Threads: Number of Threads are the hardware ability of a processor to execute that many logical processes within a single core or processor. More the number of threads, more instructions can be executes on the same processing unit.
• Clock Speed: It is the frequency at which the CPU executes the instructions. It is measured in billions of cycles per second (GHz). This determines the actual processing speed of the processor. But, having a processor clocked at 3.4 GHz isn't the sole factor to guarantee a fast computer.
• CPU cache: Integrated on the CPU die itself, the CPU cache is the fastest memory unit of the system. It is responsible to make the processing of data faster in processes where data has to be transferred between the processor and the RAM.
• DMI/FSB: Direct Media Interface or DMI is the technology that is used in Intel's i3, i5, i7 processors that has separate channel of buses for transfers to and fro. One channel each is provided for RAM, PCI-E and other devices. Front Side Bus or FSB was the technology that was used in processors prior to i3. FSB has a single channel of buses for transfers to all the components and devices of the system.

Rest of the specifications to be continued in the next post.

Specifications of a Hard Disk

Hard Disks have a few performance specifications that a buyer must always know accurately before purchasing the hard disk. Better specs will obviously make the system perform faster. The specifications are:

• Capacity: The amount of data that the disk can store. Usually 100's of GB's or TB's.
• Cache: A small memory chip that stores a fraction of frequently accessed data that can be accessed extremely fast. Usually 8 or 16 or 32 or 64 MB.
• Spin Speed: The speed at which the hard disk platter rotates. Usually, 5400 or 7200 or 10000 rpm.
• Average Seek Time: The average time in which the R/W head can be positioned over the requested track for random read/write requests. Usually, ~8-10 ms.
• Average Latency: The average time for the disk to rotate the platter and position the correct sector under the R/W head. Usually, ~3-5 ms.
• Interface: The interface that the hard disk uses and the port that it will use to connect to the system. The interfaces also have transfer speeds of their own. For example, a max. of 167 MBps for IDE, 600 MBps for SATA.

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.

Cache: Types and Functions

Cache is the memory area where a part of the most frequently (more frequently than data in the RAM) is stored.

Caches were introduced to further enhance the mismatch of various hardware components of the computer like that of the processor and peripheral devices.

The purpose of caches is simple. They enhance the speed of a computer's hardware and software parts.

Cache is of two types: Hardware and Software.

The hardware caches are usually memory chips embedded within a hardware device. The most common example of this are the L1,L2 and L3 caches of modern processors.

The software caches is the ability of the software to save the most accessed user data on the Hard-Disk or the RAM. An example of this is the internet browser cache that contains cookies, form data and partial website data.

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.

Ports for storage devices

Computer systems have a variety of secondary storage devices, some essential and the others optional. Some of these include hard-disk drives, optical drives, tape drives, floppy drives, etc.

For the transfer of data to and fro from the devices controllers are required to control the ports for connecting the devices. For the ports already present in the motherboard, usually the controller is on-board the motherboard too. The ports for hard-disk drives and optical drives include:

Parallel ATA (PATA/IDE):

• 40 pin cable and port
• max cable length: 45cm
• max number of hard drives: 4 (only in some motherboards, 2 per cable)
• max transfer speed: 133 MB/s

Serial ATA (SATA):

• 7 pin cable and port
• max cable length: 1m
• max number of hard drives: 8 (till now, one per cable)
• max transfer speed: 150-600 MB/s

SATA ports are fast replacing PATA ports. Controllers for extra ports like additional SATA or PATA ports, SCSI, USB, etc. that have been added via PCI card or similar are built on the PCI card itself.

There are ports for additional storage expansion as well like USB and SCSI. SCSI is mainly used with servers that have large arrays of hard-disk drives whereas USB controller is already present on the motherboard. The latest USB 3.0 specification is supposed to achieve 600 MB/s.

PCI-Express: why it is better

PCI Express or PCIe is an expansion card standard that was designed to replace the older AGP, PCI and PCIx bus standards. The PCI-Express standard offers higher system bus throughput and has lower I/O pin count.

PCIe has serial links between devices called Lanes, unlike the parallel connections present in PCI buses. PCIe can be a x1, x4, x8 or x16 type where the number equals the number of lanes. ( D,E : ports and sockets of a motherboard )

The PCIe (common revision 2.1) has a bandwidth of 16 Gbps for a 16 lane link (x16).

PCIe slot can be used for placing expansion port card, modems or sound cards, etc. But, Graphics performance can benefit the most with the use of PCIe because they require the maximum bandwidth for transfers. So, the graphic cards (or GPU) are built for and placed in PCIe slots.

PCI: Peripheral Component Interconnect

The PCI refers to the computer bus for attaching hardware devices in a computer. These devices can take either the form of an integrated circuit fitted onto the motherboard itself, called a planar device in the PCI specification, or an expansion card that fits into a PCI slot. ( A,B : ports and sockets of a motherboard )

Typically, PCI cards used in the expansion slots of a PC include network cards, sound cards, modems, extra ports such as USB or SATA, TV tuner and disk controllers.

The common specifications of PCI ports are:

• 32 or 64 bit bus-width
• 33.33 or 66.67 MHz synchronous clock
• transfer rate of 133 MB/s for 32-bit
• 32- or 64-bit memory address space (4 GB or 16 EB)
• 5-volt signaling

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

Motherboard : graphically revisited

In the post meant for the introduction of the Motherboard, we discussed it is called so because it is the backbone of all the components of a computer system. One of the most important point for assembling a computer is the knowledge is to know all the ports of the Motherboard.

This post is only dedicated to studying the placement of various

chips and ports present on the Motherboard with the help of good hi-def images..

In the next post, I'll write in detail about the ports of a Motherboard.

Extra Credit- IC3 information

When? 10 a.m
Where? In the state of Mississippi
Amount? $35.00

Journal Entry

   In this semester in Computer Fundamentals I learned, keyboard shortcuts, basics of Microsoft Office Software, and the difference between Microsoft and MAC. Now that I have learned these things, it is easier for me to do projects, and it now takes me less time to get from one web page to another.

   Technology is used for many things. It is even used for careers you may want to pursue. Some of these careers may be a Radiologist, because it has to do with doing X-rays and in order to do an X-ray you need a computer. Even applying or interviewing for a job you may need technology. The most commonly used software is Microsoft Office Powerpoint. In that program, you can make slideshows, it can be used for showing information and stuff.

   I would love to continue studying about the Academy of Apple. I would like to continue learning about Apple because at the pace that Apple is going, mostly everyone will be using it somehow. So it would be nice to know a lot about it to help others. And it is also an advanced type of technology and is very common.

Journal Entry

   In this semester in Computer Fundamentals I learned, keyboard shortcuts, basics of Microsoft Office Software, and the difference between Microsoft and MAC. Now that I have learned these things, it is easier for me to do projects, and it now takes me less time to get from one web page to another.

   Technology is used for many things. It is even used for careers you may want to pursue. Some of these careers may be a Radiologist, because it has to do with doing X-rays and in order to do an X-ray you need a computer. Even applying or interviewing for a job you may need technology. The most commonly used software is Microsoft Office Powerpoint. In that program, you can make slideshows, it can be used for showing information and stuff.

   I would love to continue studying about the Academy of Apple. I would like to continue learning about Apple because at the pace that Apple is going, mostly everyone will be using it somehow. So it would be nice to know a lot about it to help others. And it is also an advanced type of technology and is very common.

My Future !!!!!! :-)

Plan A- Dance Instructor
Plan B- Lawyer
Plan C- Radiologists


Plan A- Dance Instructor...
 - Colleges:
1. CUNY Hunter College; New York, NY
2. Marygrove College; Detroit, MI
3. Emerson College; Boston, MA

Plan B- Lawyer
- Colleges:
1. CUNY John Jay College Criminal Justice
2. Briarwood College