System softwares

The major types of System Softwares are:

Operating Systems (OS): The Operating Systems or OS are responsible for all the user friendliness of the computer. The OS runs and makes it possible for the users to interact with the computer without any knowledge about the underlying hardware. The OS interacts with the hardware using firmwares and device drivers and the users can use the hardware using the interface of the OS.

Boot Loaders: The boot loaders are small chunk of softwares that start up the operating system when the computer is turned on. They are the first instruction sets that the CPU processes. They help loading up the OS into the memory so that the OS can start and the computer is as usable as it is now.

Device drivers and firmwares: These softwares together help us use all the hardware devices like printers, cameras, flash drives, etc. The firmwares are softwares that reside on the device itself. They help the device hardware to function correctly and give results as it should. Device drivers on the other hand, are softwares that run on your computer's OS that help the OS to interact with the device firmware correctly.

How to choose the right cabinet for your desktop?

 The first and foremost important thing to consider before looking for a desktop case is that you know the form factor of your motherboard. If you know it, very well. However, if you don't know it, you should refer to the specifications of your motherboard or check it online. It is usually of the form ATX or micro ATX or BTX or micro BTX. This is important because the form factor decides the shape and size of the motherboard and we would obviously like to buy a cabinet, that can house our motherboard.

Secondly, it is a must that you buy a cabinet that has ample space inside. In simple words, buy a large cabinet. It promotes air flow and will keep your system cool. Thirdly, the case should not conduct electricity. Ensure that the case is not metallic and that each and every screw-hold for the components has rubber or plastic insides. This will help in preventing your system components from getting an electric shock.

Fourthly, there must be ample additional cooling fan attachment space in the cabinet. This is the first and the most critical point for gaming systems. Apart from the mandatory cooling fans present in your SMPS, over the CPU, and above the GPU, there should be provisions to attach more fans at the rear, the left side and in hardcore systems, the front as well.

Fifthly, see that the case has ample of hard drive and optical drive bays, so that you can attach as many HDD's and ODD's as you want. And optionally, look out for the optional components like headphone jacks, the number of USB connectors, etc. that help you in being more productive.

The image on the left shows a nice cabinet, with good cooling provisions.

Graphic Cards: model numbers

Writing this post in response to the guy who called me up yesterday night inquiring about two graphic cards (GPU's) and among the two is better. The GPU has specifications that need to be compared to decide which among the available ones is the best. However, there is a short-cut that can roughly point you to the right card. This post explains about that short-cut. As you might already know, there are 2 big players in the GPU market, nVidia and ATI. Let me start with the help of an example from both.
Firstly let us pick a GPU, let's say nVidia GeForce GTX 580. The model number 580 has three digits:

• 5 - It represents the family of the GPU. The higher the number, the latest technology it uses and that it can support.
• 8 - It represents the performance of the card. The higher the number, the better and faster it can compute.
• 0 - It represents trade-off between graphics quality and performance speed. The higher the number, the higher the clock speed but lesser quality.

Now let us pick an ATI Radeon HD 6870 GPU. The model number 6870 has four digits out of which the last digit is insignificant:

• 6 - Same as in nVidia, it represents the family of the GPU. The higher the number, the latest technology it uses and that it can support.
• 8 - It represents the performance of the card. The higher the number, the better and faster it can compute.
• 7 - It represents the stability and reliability of the card. The higher the number, more stable it is.

Obviously, the lowest model number would cost the least. But, since we do not want outdated technology, it is necessary to buy the right Graphic Card out of our available budget. Choose a higher performance graphic card if you want to play the latest games flawlessly, but choose a newer graphic card if you want to extend the life of your PC. Sometimes, u might face a dilemma when you go GPU-shopping. For example, you might find the price of nVidia Geforce GTX 480 and GTX 550 almost similar. The choice is yours, but remember the points mentioned above and you will add a gem to your system.

Specifications of an Optical Drive

Various types of optical drives are available in the market. These include CD readers, CD writers, DVD readers, DVD writers, DVD combos, BD readers, BD writers and BD combos.

The specifications of an Optical Drive drives to be considered are:

Supported Media Types: The optical drive must support a major part of available types of discs in the market. Examples are CD-ROM ,

DVD-R ,DVD-ROM ,CD-RW ,CD-R ,DVD-RAM ,DVD-RW ,DVD+R and DVD+RW. Note that CD drives do not support DVD's or BD's and DVD drives do not support BD's. Also, the supported media types are different for a drive's read and write capabilities.

Interface: The interface that an optical drive uses and the port that it will use to connect to the system. The interfaces have transfer speeds of their own. For example, a max. of 167 MBps for IDE, 600 MBps for SATA. But, the current technologies available for optical drives can only provide speeds that are lower than modern systems. So in case, both the ports are available in your system, the interface is not much of a specification.

Buffer Size: The optical drive buffer works in exactly the same manner as the cache of a hard drive It stores a fraction of frequently accessed data that can be accessed extremely fast. It helps the system to access data from the drive even if the processor is being utilized 100% by other processes for a fraction of a second. Usually 1 or 2 or 4 MB.

Read & Write Speeds: All optical drives have different read and write speeds and different read or write speeds for different types of media. For example, DVD drives have a speed of 16x, 20x, 24x (where x is 1.35 MBps) and CD drives have a speed of 32x, 48x, 52x (where x is 150 KBps). An optical drive will always write different types of media at different speeds (For example, a CD at 48x, a DVD at 16x and a re-writable DVD at 4x). 

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.

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: 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.