*Image courtesy of Iamnee / FreeDigitalPhotos.net

*Image courtesy of Iamnee / FreeDigitalPhotos.net

Memory consist of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of process data. Memory usually consist of one or more chips on the motherboard or some other circuit board in the computer.

The computer memory stores three basic categories of items: the operating system and other system software that control or maintain the computer and its devices; application programs that carry out a specific task such as word processing; and the data being processed by the application programs and resulting information. The role of memory to store both data and programs is known as the store program concept.

The basic storage unit in memory is known as the byte(character). When application program instructions and data transfer into memory from storage devices, the instructions and data exist as these bytes. Each bite resides temporarily in a location in memory called an address. Okay let me give you an example; let’s say you have entered a classroom, that particular classroom has 36 seats and all of them are empty. The teacher enters his or her seat; that’s one chair down. You have entered another seat; which is another taken up. Now you have 34 seats left; also take note that each seat is numbered and labeled. Now the rest of the class comes in and fills the rest of the seats. Now you have a full classroom with all seats filled in. Now when the class session is over, all the seats have not been emptied for that day.

Now let’s put this into computer terms: an address in memory holds one single byte; both the seats and the address can be empty; the seat has an unique identifier and so does a memory address. To access all of this data in memory, the computer references the address that contain bytes of data. This is much similar to the teacher asking a student to perform a task. If a student lazes about, they get punished. Well in a computer term, if a byte is not performing its task then it goes towards another bite in the address. Storage devices hold data and instructions for future use, while most memory holds these items temporary.

The system unit contains two types of memory, volatile and nonvolatile:

Volatile memory is memory which contents are lost when the device is powered off. RAM is thia and, as a result, serves as a short-term storage location. It requires power to retain stored information which means that this is vastly more expensive per unit than its counterpart, but much quicker to access, hence its use as temporary memory. That’s WHY the bytes tend to be lower; a few GBs these days for now.

Non-volatile memory however does not lose its contents when the power is removed from the computer. ROM is this and as a result serves as long-term storage. Think of it like your brain storing information when you read a book or retaining information on what is said or what happened to you. It stays in your brain for quite a while and in some instances, the actions you take from remembering what happened comes like clockwork. Uses are typically referring to when somebody asks you about non-volatile memory, they are talking about storage devices such as the hard drive, flash disks etc. and the only way these can be removed if the user deletes the information on them. The other way which is worse happens to be magnets as they corrupt data when you put them near said storage devices.

Well this is about covers it about the memory of a computer.

*Image courtesy of koko-tewan / FreeDigitalPhotos.net

*Image courtesy of koko-tewan / FreeDigitalPhotos.net

Graphic cards also known as video cards, graphic adapters or display cards are what you see while you use your monitor. Computers today mostly come with the video controller with the video part integrated onto the motherboard. If you are having problems with integrated graphics than today’s computers can easily install a graphic card and bypass the built on internal one but make sure that you can disable the controller on the motherboard if it gives you trouble. That is one scenario but if you need to install the graphics card ironically the integrated one was still work in helping you out by displaying what you are doing to install the graphics card. Just make sure that you have the installation files that came with your graphics card if you have bought it from a computer store.

Now take into consideration, the number of colors a video card displays is determined by its bid depth, which simply means the number of bits it uses to store information about each pixel. Let’s say for example and eight bit video card uses eight bits to start information about each pixel. At the end of it, only 256 colors can be displayed. The more bits a graphics card has the better the display. This is why so many applications that use video or graphics demand more and more bits of data coming in. If you ever wonder why people that want high definition movies and clear display crave for that experience, now you know. That’s the same with game enthusiasts wanting more and more quality experience when playing their games either off-line or online.

Now let’s look deeper into what a graphic card does when sending information to a cathode Ray tube(CRT) monitor. In another blog post I mentioned that the processor is the brain of the computer. Well, it sends that digital video data onto the graphics card. The video card digital to analog converter(DAC) converts the digital video data to an analog signal. Then it gets sent to the cable onto the monitor which separates the analog signal into red green and blue signals. Electron guns fire these three signals to the front of the monitor and then the image is displayed on the screen when the electrons hit the phosphor dots on the back of the screen. Remember, this is the explanation for CRT monitors and the basic instructions the processor use to send to a video card. Although LCD monitors also uses a processor and sometimes a video card, they work quite differently and the analog signal reverts back to digital.

Okay the way LCD works is this, first a panel of florescent tools emits light waves through a polarizing glass filter, which guides the light towards the layer of cells. Second, as the light passes true and electrical charge from a transistor causes some of the cells to twist making the light waves bend as they pass through a color filter. Third, then the light reaches the second polarizing glass filter light is allowed to pass through any cells that line up at the same angle as the first polarizing glass filter. The absence and presence up current like costly image appear on the display. I would like to state otherwise but facts is facts no matter how it is put. The processor sends a digital video data in almost the same way to the video card to LCD monitor. Laptops, smart phones, and other devices that utilizes LCD goes to the same format.

I hope this about covers it about what a graphics card in the computer is. It is complicated a bit but now you see why and I try explain as best as I could.