Advanced Hardware Info

[Gogeta70]

Hey everyone, this topic is just about how hardware works. I'm writing this for anybody interested, so here goes.

RAM (Random Access Memory)

As many of you know, the processor uses transistors to work. Well, RAM works very similarly. Particularly, there are 2 different types of RAM, SRAM and DRAM. SRAM, or Static ram is more expensive, and uses capacitors to work instead of transistors, but most computers today use DRAM, or Dynamic ram.

RAM has 2 major pipelines, RAS and CAS, which stand for Row address select and Column address select. You can imagine these pipelines like a grid, where the RAS pipelines run parallel to the X axis and CAS pipelines run parallel to the Y axis. These pipelines are used to access each individual transistor inside your RAM, either to read or write a charge to them. However, because transistors don't hold a charge for more than a few microseconds, your computer has to send a charge down each CAS and RAS pipeline to recharge the ones that hold a charge. This is what causes CAS latency.

Also, you may notice that when you look at a stick of ram, it has black rectangles on it. Each of these rectangles holds a certain amount of transistors. Also, if you have an odd number of black rectangles, it means you don't have parity, and if you have an even number, it means you do. (unsure about this, it may be odd = parity, even = no parity). Parity is a physical implementation into your ram to check for data errors.

Processor

The processor, like RAM uses transistors to store and process information. The processor is actually split into several sections, for instance the Floating point unit, and the L2 cache.

Unfortunately, this is about all i know about CPU's, so i'll need to do some more reading up.

Graphics Cards

Graphics cards are mainly like miniature motherboards. They consist of their own RAM, processor, and BIOS. Graphics cards were created for the reason that the processor had a hard time handling, Visual, Audio, and other computing tasks all at once. Originally, graphics cards were used in ISA 16 bit slots, just like other regular add-ons. But eventually, graphcis became so advanced that they created AGP, and later on PCI-E. Along with that, Graphics cards usually had 2 different processors. The 2d processor and the 3D processor. After a while though, 3d graphics became so intertwined with 2d graphics that they integrated both capabilities into one processor.

Graphics cards are most often used in AGP slots, with are created to handle more information per clock-cycle than regular PCI slots. These AGP slots are connected to the North bridge of the motherboard, which has higher priority than anything connected to the South bridge chipset.

There is a newer type of slot out for graphics now, however. The PCI-Express slot, which can handle up to 2 gigabytes of graphical information per second! Not only that, but if you really want some cutting-edge graphics, you can connect 2 PCI-E graphics cards to eachother (have each card in a PCI-E slot, and connect them with a certain wire), which is called bridging. This will allow the cards to combine their processing and RAM power, which calls for almost double performance.

Motherboard

The motherboard is what holds everything together. Kind of like a human body, you can have your legs and arms, but you can't do anything without your torso, or head. Everything connects to the motherboard, the CPU, RAM, hard drives, pci/agp cards, everything. Because the motherboard has to handle so many devices, it assigns each device something known as an I/O address. Kind of like an address to your house, it is a unique number to refer to that specific device. The motherboard also has something called the North bridge and the South bridge. The north bridge is connected to something called the interrupt wire. The interrupt wire goes directly to the processor and gives it a device I/O address, which the processor then gives attention to that device. The north bridge houses only a few devices, mainly the RAM and Graphics card, so that they may access the processor before any other device.

The south bridge is connected to the north bridge, and houses all devices that the north bridge doesn't. This means the mouse, keyboard, pci slots, hard drive, disc drive, etc. However, because of all these devices, there is a good chance that many devices are going to request processor time at once. Therefore, we have the IRQ number, or Interrupt Request number. Each device is assigned an IRQ which gives it higher priority over other devices with a higher IRQ number.


Note: I may continue developing this article later on, so keep checking up on it.

[floodhound2]

Nice job man. Easy to read and not to complex yet for the noobs out there.

[Gogeta70]

Thanks.

[shamir]

very good man, keep up the great work, very helpful.