I helped a friend
last week assemble a bran-new computer and he was interested to learn
how it's done.
A quick search on
the Google machine showed mediocre results for learning PC basics so
I thought a quick write-up would be in order. I started tinkering on
computers when I was in Jr.-High, and in high school I built my first
computer. It was just school-tech leftovers that they used for the
students to practice on but I had a pretty good start to this hobby
of mine.
There are two parts
to a PC: hardware and software. I'm not much on software and most of
it these days is pretty user-friendly and simple so I'll focus on
hardware for this write up. Basic parts for a system include the
Motherboard, the PSU, CPU, the RAM, the GPU, the HDD, and the optical
drive or ROM.
The Motherboard is
where it all comes together. Its what flows all the data from on
center to another. There are various ports, expansions, jumpers,
chips, etc. Main components of the motherboard are the socket, the
DIMMs, the IO, the PCI expansion ports, chipset, SATA, IDE, various
headers, jumpers, and a battery. They come in various form factors
and vary widely in features and capabilities.
Pictured above is the MOBO's Model Number (very useful for finding specs drivers and QVLs)
The socket is where
the CPU installs. You can only install compatible CPUs into a
socket.
DIMMs are where the
RAM installs.
The IO are the ports
on the rear of the motherboard for plugging in peripherals such as
your keyboard, mouse, speakers, etc.
The PCI expansion
slots are where additional functionality can be installed such as
discrete graphics, TV cards, WIFI cards, etc. There are PCI, PCIe,
PCIe4x, PCIe16x, AGP, PCIe2.0 and PCIe3.0. PCIe16X, 2.0 and 3.0 are
backwards compatible. Your card will run properly, but the bandwidth
is dumbed down to match the slot it's in. (Pictured above are PCI slots and the brown one is an AGP)
The chipset is the
main chips that direct the flow of data between the ROM, RAM, and
CPU.
There are various
headers for USBs, Audio, fan headers, and power switches with their
associated LED indicator lights. The USB headers are used for front
mounted USB ports and card readers. For MOBOs with built-in audio
you can connect front audio jacks to those audio headers. Then there
is the header for the power switch, reset switch, power LED and HDD
led.
There usually are
various jumpers for certain feature control. I have a MOBO that
allows you to limit CPU FSB speed with a jumper. Most MOBOs have
jumpers to adjust power output to USB headers. One of my PCs I can
charge my cell phone with the USB even if the PC is powered down.
And also another important one is the BIOS reset jumper. Helpful if
your BIOS become corrupted or you change a setting that doesn't work
out.
The battery is
important. It may just be a stupid little button battery but it's
what keeps the system clock running, and the bios settings saved. I
have a MOBO that I used for a while, then tucked back in the box for a
later day. I recently got it out to use it once more and when I
booted it up it had it's old settings still and the time was correct.
Two Fan headers (the white plugs)
SATA and IDE are the
interfaces in which the storage devises are controlled. SATA is the
newer, faster interface. IDE (or PATA) are the old interfaces. They
were the big ribbon cables that are so obnoxious.
SATA (top) IDE or PATA (bottom)
The difference between an old IDE ribbon cable and a newer SATA cable.
Pictured above is the BIOS chip
I neglected to take a photo of a PSU, so apologies for that.
The PSU is simply
the power supply (unit). They can come in several form factors and
typical power output is read on the PSU as watts. There are
standard, semi-modular, and fully-modular PSUs. A PSU can have any
number of power outputs on it. Motherboard power, CPU power, Molex
connectors, SATA power connectors, PCIe power connectors, etc. Modular models help keep the interior of the case clear of a mess of wires.
There are also power efficient models rated bronze, silver, or gold
for those of us interested in saving some money on our electric bill.
I see them as a good option if the PC is in use often, runs all the
time as a server, or if you have a computer lab and run many PCs.
They are also more expensive. Hence why I've never owned one. That,
and my PCs or only powered on for as long as I use them.
Old AMD Athlon XPs on top, Pentium 3 and a Pentium Celeron in the middle and two Pentium 4s on the bottom.
The CPU is the brain
of the Motherboard. Raw data goes in and calculated data comes out.
When you execute a program the data is received by the CPU as a set
of instructions. The CPU executes those instructions. There are
single core, duel core, triple core, quad core, six core, and 8 core
CPUs. Some CPUs have integrated graphics processors and AMD makes
one with 12 cores. 4 CPU cores and 8 GPU cores. CPUs can only go in
their associated sockets. AMDs series of am2, AM2+ and AM3 sockets
are backwards compatible. You may use an AM3 processor in an am2+
socket, it just dumbs down the Front side bus speed to the socket's
limit. There are two speeds to consider with CPUs. The CPU's speed
itself, and the Front Side Bus speed. The speed of the CPU is how
fast it can make calculations or run sets of instructions, or a
better way of saying it is how quickly it can process data. General
rated in ghz. The front side bus is how fast it can transfer that
data to other parts of the motherboard. The more cores mean the more
instructions or calculations it can do at a time. The faster the ghz
the faster it makes those calculations or finishes those
instructions. A duel core CPU can accomplish a task faster then a
faster rated single core because it can have 2 cores work on it
together. The enemy of a CPU is heat. CPUs come with coolers
usually made of aluminum or copper or both. They draw the heat off
the CPU chip so it can maintain it's stability. Sometimes if your
computer is running sluggish or crashes for no apparent reason it can
be as simple as opening up the computer and removing dust build up.
I'm a bit of a nerd for air-cooling and the PC I'm building now has 9
fans and the biggest CPU heat-sink I could find that was both well
rated and affordable.
The RAM is very
important to the CPU. When the CPU is running instructions or
calculations, it stores the data in the RAM. Random Access Memory.
One of the best ways to speed up a computer is to add more RAM, or
faster RAM. There are a few types of RAM, and none are compatible
with each other (DDR, DDR2, DDR3, SDRAM, DRAM, and so on). RAM comes
in different speeds measured in MHz. The more RAM, the more it
costs, same with the faster the RAM. I think DDR4 RAM hit the market
recently. 32 bit versions of Windows can only recognize up to 3
gigabytes of RAM. 64 bit versions don't really have a limit. I've
seen motherboards with support for up to 64 gbs of RAM. I personally
don't have a computer that currently runs more than 4 gbs. Though I
plan to have 8 when my Frankenputer MKIV is complete. I could also
easily double the RAM in my wife's PC to 8 gbs.
RAM pictured below:
The top two are DDR2 RAM sticks and the bottom 2 are PC133 Ram sticks.
Notice how the second and fourth one are single channel (RAM chips on only one side of the stick)
The GPU is the
graphics processing unit. Many motherboards have some sort of
on-board graphics built it and are fine for basic computer use or use
that does not denote heavy graphical requirements. Some graphics
GPUs are built into the CPU and can perform better than those built
into the MOBO. Both are called integrated graphics. Optionally you
can use discrete graphics. With means the GPU is separate from the
MOBO. These are additional cards that plug into a PCI slot of some
kind (or AGP for certain generations of MOBOs). Typically this
option is for gamers, or people who do graphical heavy type computer
work like 3D rendering and stuff like that. There is also a way to
combine integrated graphics with discrete graphics for further
performance. Exclusive to AMD products only it's called “Hybrid
crossfire” and is useful when graphical performance is required in
limited space. Both AMD and Intel GPUs can do a duel GPU setup.
AMD's being called crossfireX and intel's being called SLI. The
cards have to be compatible, the motherboard has to support the
feature among other things. You get extra GPU performance when 2
GPUs are working together. I imagine it being similar to when CPU
cores work together. GPUs themselves, seem to me, like little mini
motherboards. They have their own processor, and their own RAM.
(Integrated graphics borrow RAM from the MOBO) There are other specs
to consider such as the interface generation (PCIe16x, PCIe2.0, etc.)
shader cores, RAM speed, and so on. I'm still wrapping my head
around all of this sort of stuff so I can't make any conclusions at
this time.
Pictured below are some expansion cards. Top is a Video Card (GPU) in the AGP interface.
Below that is a sound card, and below that is a wireless card. To the right is a USB expansion card.
Below is some differences between 2 standard PCI interfaces (black and blue/green) and AGP (red)
Below are the IO ports on the 4 expansion cards.
HDD is a Hard Disk
Drive. There are a few different form factors and interfaces. I
have 1 HDD in a 5.25” size. It's old, slow, and only 19GB. I have
about 10 PATA 3.5” HDDs, a few SATA 3.5” HDDs, 4 PATA 2.5”
HDDs, and a 2.5” SATA SSD. HDDs are usually measured in size and
speed. For Example: 80 GB size, 7200 RPM speed. 7200 RPM speed is typical. You
get the best bang for your buck with that speed. Faster HDDs get
expensive fast. Slower HDDs can bottlneck a system. The HDD is
where your data is stored. The inside of an HDD are shiny disks
where magnetic needles write the data onto them. (Don't have magnets
near you computer, HDDs, or anything of the sort.) HDDs are usually
pretty sturdy and can last a very long time. Sometimes they go out.
I've had about 3 go out on me in my lifetime. It's always a good
idea to have a separate HDD for backups. Sometimes an HDD that is
going bad can be repaired with an
old-fashioned-write-everything-to-zeroes type format. An SSD is a
Solid State Drive. Where instead of magnetic disks it uses flash
memory chips, much like a USB Jump Drive. They are faster, cooler,
lighter, quieter, and more power efficient than HDDs. There is no
disk to spin thus it's faster, produces less heat, weighs less, draws
less power, and produces no noise. They are extremely expensive. I
bought an SSD last year for 60 dollars and it is a 120GB. Just last
week my friend bought a 1TB HDD for 55 bucks. That is more than 8
times the memory for less cost.
Below are 3 Hard Drives. All PATA (IDE) interface. Left to right is a 5.25" HDD, a 3.5" HDD, and a 2.5" (Laptop) HDD. 5.25 HDDs aren't very common.
The PATA and Molex and jumpers found on the rear of IDE drives. The Jumpers are for setting the drive as a Master or a Slave.
Here is a 2.5" SSD.
It uses SATA connections making for a much slimmer interface.
Optical drives, also
known as ROM drives are almost fading out. Streaming, downloading,
and flash memory are the new thing. ROM means “Read Only Memory”.
That Blue-Ray movie you bought the other day is ROM. Meaning you
cannot pop that disk into your computer and change the data on it.
Same goes for CDs, DVDs, HDDVDs, etc. There are some CDs and DVDs
that are re-writable but it still requires an entire disk erase to
do. Another thing that I think phases out ROM is the ability to
write ISOs, or disk images. Your HDD is faster than your ROM drive.
You can use your ROM drive to rip an image of the disk to your HDD,
you can then mount that disk's image in a virtual drive that doesn't
really exist and your PC will play it as if you had just popped in
the disk. Only now it will play it faster. And you don't actually
have to keep the disk on hand anymore. Having ISOs can eat up HDD
memory space quickly though because they are essentially
uncompressed. And if your HDD burns out, so does your data on it.
So there are pros and cons to everything.
Top Drive is an old PATA CDRW. It can only read, write, and re-write CDs. Below it is a BlueRay ROM. It can read BlueRay. It can also read, write, and re-write DVDs. And it can also read, write, and re-write CDs. Notice how the old CDROM has a headphone jack, two buttons, and a volume knob. These old drives could play music CDs without software directly to that audio jack. A feature I used frequently in my high-school tech classes. Running Music software in addition to the CAD program I was learning slowed the system down. This feature solved that for me.
Below are the PATA and SATA interfaces of the same drives.
One last thing. Earlier I mentioned a QVL. That is a "qualified vendor list". Every motherboard has one. Just because a MOBO says it takes DDR3 RAM does not mean it will take just any DDR3 RAM. When you build a system I recommend doing the following: Decide on the form factor, find the best MOBO in that form factor that fits your budget and specs, download the QVL and purchase your CPU and RAM based off of what that list says is supported by the MOBO then go from there. Returning hardware takes time and costs money.
Well, in a nutshell
those are my hardware basics. Some time in the future I'll do a
software basics. I'm not a programmer, nor do I write code. But I
can install an operating system and have a pretty good library of
free PC software that I would call a must have for those who want to
tinker with PCs.
Byebye.
Here we see the disk was partially fragmented
This will take you to the Control Panel Screen you need to click on "remote settings"
