Friday, March 30, 2012

Build a computer and save hundreds of dollars. Part 1: shopping

People don't know...but apparently when you get a computer, you pay a lot for preloaded software you don't need.  You also pay for the labor for building the machine.  If you do your homework and know what you buy when you buy the computer, you might be paying for honest labor and an honest price.  However, for the most part, too many people don't know what they get.

I grew up with the tech trends.  I messed around with an Apple IIe when I was six.  I built thirty-six computers in high school in one batch.  I went to med school instead of going into computer engineering...but computers are a part of life.  However, they are a tool.  They are only as smart as their users.  Unfortunately, there are plenty of smart people whose minds bork at the modern computer.  The thing is, it's not so fundamentally different as long as you do a little research.  So, let's build you a new machine.

I make no money off of my brand reccomendations.  Also do look at the date on my article, as the specific brands do change.  However, if I plan this right, the algorithm should still be sound.

Planning:
1) General vs. specific purpose?
If I ask you what you want your computer to do, and your answer is 'I don't know,' you're asking for a general purpose machine.  This is a balanced computer, not a lot of extravagance, but you don't want to be shorted on resources that will actually help.  Specific purpose machines are built for people who know EXACTLY what they want.  These are the people who aren't reading this.  Next step...

2) Conventions and scale
What people need to know when buying are what the numbers really mean, and what practical scales imply.  A few values are important, some can be varied, some have lower limits.  If you have unlimited $$$, go for broke...but I'm trying to save some cash here.  A newbie reading this can get a high-end system, know that it can do the job, and if he doesn't work it to the nth degree, it'll last a good long time...four years at least, over the two years expected.
Currently, as of 2012, there are some reccomendations on different variables.  I'm going to talk you through them.

Hertz:
simply, cycles per second.  This is a measure of raw speed, and requires a bit of mind-expanding stuff.  Everything that goes on in a computer is based on math.  Imagine doing your budget or working your taxes or even writing stuff by hand on a page.  You could consider each action (doing a math problem or writing a sentence) a process that can be done in one unit of time, that is, a cycle.  In fact, this is how programmers write the instructions (programs, software, applications).  Each line of code (the stuff a programmer writes) roughly equates to something the computer carries out during a cycle.
Now...the operating system, plus the user interface (the stuff that you actually interact with in order to tell the computer what to do) runs in a loop, ready and waiting to accept commands.
Each second, the computer executes two to three billion cycles...that is, operations...every second.  That's why it's measured in hertz...2-3 giga (billion) hertz (cycles per second.)
So, why should you care?  Simply put, it's an unfortunate issue of the technology curve and the kind of computing power that the industry expects the consumer to have.
 HOWEVER...the industry does not want to leave the consumer behind.  What's more, before I got into med school, I worked in retail, and the industry had a love-hate relationship with people like me...I sometimes talked people out of a sale...to get a satisfied customer that came back for a sale they would want and were satisfied with.
So...this first part is kind of mind-boggling unless you spent some time either growing up with the technology or in a computer science class.  However, there is a sound analogy:
A car.
Motor vehicles can be assessed in two key variables: torque (how much acceleration you can get out of the chassis) and brake horsepower (once you get it moving, how fast can you move it).  If you think of a computer as a car in terms of overall performance, the CPU is the engine.  (The CPU is, in fact, the backbone of the system on many levels, but I'm simplifying it here to explain.)  The clock speed, rated in frequency (x amount of gigahertz...that's the frequency) is the raw base speed of the processor for its rated tolerance.  CPU's will always run to their rated tolerance unless the software dictates otherwise.  That's the basic brake horsepower.  The torque equates to the power of the processor, which is a function of how it's constructed.  That's a little more complicated.  The bottom line is that the higher the hertz, the more oomph you get off the start.  These days, 2.5-2.6GHz does wonders and satisfies basic needs.

That said, if you spend the amount of money asked for a low-grade computer and know how to shop, you can get a medium-to-high grade rig and, even if you don't use all the power today, it ought to keep you up to spec for a good long while.

Bytes:
Okay.  When we talk bytes, we talk storage space.  Storage space is divided two ways...volatile and nonvolatile.  The key difference...if someone pulls the plug on your computer, anything in nonvolatile storage is still there, and can be retrieved after you reboot.  (I know this from hard experience...I had medical essays set back by hours when my cat put her paw in the wrong place and shut my computer down...)
A computer is different from a calculator because it stores information in memory to be used in a later step in the program.  This memory is RAM, random access memory.  (The computer doesn't really store things randomly but it does seem that way over the course of a few billion operations.  Don't worry about how many operations...at this scale it's a measure of speed...the people who do worry about it are dedicated and established programmers.)  If you imagine the computer as someone doing your taxes by hand, the RAM is the scratch pad used for calculations.  The bigger the pad, the more stuff can be done before it has to be turned over to a new page (next cycle).  For RAM, you usually want 4GB at least.  This is a decent amount to start.  You can always add more later if you find you need it, but leave off such investments until you decide you want 'em later.  RAM is cheap as long as you look for basic stuff like capacity.  Some extravagances include built-in heatsinks, but that's for die-hard system tweakers at this point.  Let's talk about getting you started, okay?
The other bytes you need to worry about are the onboard storage bytes.  This is your hard drive.  It's a high-speed magnetic storage device that is nonvolatile (remember what I said?  If you pull the plug, anything stored here doesn't go away?).  Because of its mechanical nature it is slower than RAM, but it is more robust.
For me, I think of a cell.  The hard drive is your DNA.  To make something work, it has to copy the information into something that works faster...the RAM is your RNA.  After that, the system needs to do something with that info...so it takes it to a ribosome...
Okay.  That's a little obscure.  So, let me bring it down to earth.  You want to get information from the encyclopedia at the local library (the information on the hard drive).  But, library rules...you can't take the encyclopedia out of the library.  However, they will let you take the encyclopedia to the photocopier (encoding the information to RAM), allowing you to use it.
The more RAM you have, the more information the computer can use at once.  However, hard drives are dramatically larger by orders of magnitude (my computer has 8GB RAM...but 1000GB of hard disk space).  Why?  Because you, as the user, aren't using all of the information on the hard drive at once!  However, you want it there because it's your information and needs to be stored.
That said...when it comes to hard drive space, in my experience, you can get away with 250-500 gigabytes of space.  I have a terabyte (1000 gigabytes) and use it because I do more information-intensive tasks.  250-500 will get you started.  You can always add another hard drive.

RPM:
Wait...revolutions per minute?  Okay, this is a minor point, but something that might be important in the long run.  I throw this in here to make things clear when buying hardware.
Hard disk drives have a raw speed rating based on how fast the discs (the actual components that store the information) spin past the drive heads (the things that read and write information...if you use cassette tapes, it's the same kind of operating principle).  The faster the drive spins, the quicker you can access information.  Unless you want to go cheap, I reccomend not skimping on RPM.  You want to look for a 7200 RPM drive.

x:
8x, 20x, what does that mean?  This refers to optical drive speed ratings.  Don't worry about this unless you're buying drive media.  In this day and age we have an engineering bottleneck, and the fastest drives are inexpensive.

3) CPU
Okay.  Hopefully I haven't confused the hell out of you, but if I have, feel free to scroll back, print out, ask questions.  I'd rather be patient and have you understand.  Unfortunately I can't be there to help you so I'm going to lay things out as I've learned from experience.
First, brand names.  If you're inexperienced, I would say forget Intel.  Once upon a time, when model numbers indicated performance, I'd have gone wholeheartedly with Intel.  These days, I'm trying to reccomend cost-performance benefits by experience.  Now I'm not knocking Intel, they make a solid product.  However, what I've used now and what I'm reccomending is an AMD Phenom II.
American Micro Devices (AMD) is a decent competitor for Intel, and like Intel, they make a solid product.  AMD makes it less expensively for its performance.  Depending on when you read this, I reccomend doing some homework...look up "benchmarks," that'll point you to performance data.  Here's the deal...for fifty bucks a chip, you end up with (at last check, anyway) a 3.0 GHZ Phenom II x2 CPU.  (I'll tell you about the x2 in a sec.)  It doesn't take a lot of money to get some decent power.
Now, when it comes to CPU's, people may talk about dual-core or quad-core...the 'core' number is actually important for performance.  I have an AMD Phenom II x4, which is an AMD (make) Phenom II (model) x4 (four cores).  The physical chip breaks itself up into four processor cores, which divides the billions of tasks among them...this increases performance.  More cores can be more effective if you run demanding apps.  However, if you're not going for high-end applications (like massively powerful graphics applications, sound applications, pro-grade video software or massively powerful math programs) then a dual core (Phenom II x2) will give you plenty of power at a low price.

 4) Mainboard
The Mainboard, aka the motherboard or MoBo, is the chassis that holds the engine (your CPU).  There's a lot of choices out there.  Once you select your CPU, it narrows down the choices of mainboard by socket...that is, the compatible socket that holds the CPU.  It's not that hard...simply, will the chip fit the hole?  This is easy enough.  The CPU box will have a socket specification, and the mainboard will meet it.  This will help you figure out which boards will meet your needs.
Mainboards rarely limit your capabilities by architecture (what's on all those squiggly lines running around the board) but might limit them by engineering (the slots on the surface into which you insert cards, or items that are physically built into the board).  You will need to ask the sales rep.  Here are some things to consider:
-Do you want to expand for the future?  I reccomended 2-4 GB of RAM, but can the board handle more later?  If so, how much?
-What items are built into the mainboard?  Most mainboards at least have sound processors using Realtec or Creative chipsets (both are very good for basic needs), and some have graphics chips onboard (my computer mainboard came with an NVidia chipset, but when I bought it that chipset was bypassed in favor of a graphics card).  A lot have ethernet (also known as 10-base-T or cat-5) adapters for hardwired networking...it looks like a fat version of a telephone socket.  Sometimes the features of your mainboard may save you some money and hassle because items are already built in.
-What slots are available?  Sometimes people add in their own hardware for different functions.  You may end up picking out a new mainboard based on information you find out.  Be prepared to adapt to meet current demands.  These days tech has hit a bottleneck in physics, so you have low-cost opportunities to change.

 5) Graphics
Well, you want to see what you work on, right?
I reccomend a mid-range graphics card rather than using one built into the mainboard.  Simply put, the internet runs more and more elaborate websites, and if your internet connection handles the information, sometimes your computer will be hard-pressed to handle it.  My personal mid-range reccomendation is an ATI Radeon 4550, but the equivalent nVidia will be just as good.  At those specs it comes down to where you shop, and both will deliver equivalent performance.  If the mainboard has an onboard GPU (graphics processing unit) of equivalent power, then you don't need to buy extra hardware.

6) Cooling
I am not kidding on this.  By itself, a modern CPU can reach temperatures sufficient to fry an egg even before you start messing with the clock speed.  This is within the manufacturer's ratings.  It's also why when you get a computer there's a huge hunk of fluted metal on it with a fan on top.  That hunk of metal is a heatsink.  The fan is there to increase airflow.  If you're reading this and want to build your own computer and save some money, this is how you make a long-term investment...
LIQUID COOLING.
Now for a basic computer...you do not need an extravagant kit with lots of tubes, a big radiator, and pumps.  These days, it is simple.  I reccomend an Antec Kuhler 620, a low-maintenance pre-built system.  Sixty bucks saves peace of mind...and it cuts the operating noise.  As far as cooling the rest of the system, this brings me to...

7) the case
This is what holds everything together.  You have the backbone, the engine, the chassis, but you need a skeleton.  Now, case sizes run in mini, mid, and full tower designs, with more exotic assemblies.  I would reccomend a mid-tower...it's a reasonable size with plenty of space to build, and it's not overly huge.  Full-tower designs have lots of space but...can get extravagantly BIG.
In a good mid-tower case you want 3-4 large drive bays (these are the 5.25" bays) for your CD/DVD/BluRay drives and one or two 3.5" bays for your hard disk drive (although a mid-tower case will have several more).  Most importantly...you want airflow.  A good case will allow airflow through the system in a consistent direction.  Most cases are arranged so that most of the airflow will run lower/front to upper/back, drawing air over the components and exhausting heat from the case.  These cases will often come with a couple of fans mounted strategically to propel air through the case.  (The liquid cooler I mentioned earlier can have its radiator mounted in place of one of these fans so that it does double duty, moving air through the case and also cooling the radiator...it's worked for me.  This mounting displaced one of the factory fans, but I mounted it so that it draws air past the RAM to keep those modules cool.)
With people concerned about whether they put things together right, I reccomend a windowed case.  If you buy a simple case, an acrylic window isn't that much more expensive, and allows you to view the interior of the case without opening it.  (I use an NZXT case, not too expensive, comes with two pre-mounted fans and an acrylic window.)

8) Optical drives
When I grew up with computers, I remember when the CD-ROM was a big deal.  I also remember the 7th Guest, a game which pretty much sold the CD-ROM to the public, and became a proof of concept that turned this media from an extravagance into a reality.  The optical drive is what you're going to need in order to install software, and perhaps create archival copies of your data for backups.
These days, you can inexpensively acquire a single optical drive that handles reading of CD's and DVD's...and also accomodates writing of writable and re-writable media.  (Ideally, you want something which can write to CD's, DVD+/-R and RW.  That handles all common media, and saves you the headache of looking for specific media for your drive.)

9) Power supply
Well, you can't just plug this into a wall just yet.  You need an AC-to-DC converter system which delivers appropriate volts to each part of the computer and won't overload.  Now...unless you decided you want a high-grade gaming graphics card, I would suggest you look for a power supply with a minimum rating of 300 watts.  This will power the mainboard, CPU, graphics (whether on the mainboard or a graphics card), hard disc drive, and optical drives, as well as cooling systems including fans and a pre-built liquid cooler.  If you use a higher-end graphics card, you will have to consider a higher-rating of power supply...as well as its configuration of rails.  (Each "rail" is a circuit handling a specific volt/ampere combination.  The volts are specific to the components to which the "rail" can connect.  The amperes are an engineering limit of the power supply.  In most applications, power supplies are easy.  But, if you put in a high-end graphics card, look at the system requirements or consult with the sales rep to be sure you meet the power requirements.)

10) Extras that might be a good idea
Some people might call this extravagant, but I like to have these for peace of mind and utility.  I've used them before many times.
One of these extras is an automatic fan controller with thermometer.  I reccomend an electronic automatic system because it KEEPS THINGS SIMPLE.  The one I use is an Aerocool FP-01 becaue it only occupies one 5.25" drive bay and can be set for automatic mode, allowing all onboard fail-safes to communicate.  As long as the CPU sensor doesn't exceed 65C, I'm happy.  (When I really work my computer, I rarely see the temperature exceed 37C, and most of the time it hovers around 30C...I set the alarm at 65C so that I have plenty of time to shut down before catastrophic failure, allowing me to shut down and save the hardware and software.)  Bear in mind that this is only peace of mind.  You have to spend extra to make it an insurance policy, including features that produce a second automatic shutdown in case of overheat.  (A note here...most if not all mainboards and CPU's have this kind of fail-safe already built in to prevent damage in case of cooling failure.  The sensors are built into the board and/or the processor, and kick in at a factory-set temperature, or in case the CPU cooling fan fails.  The fan controller for the novice is a reassurance...as long as they install it properly.)
Another extra is based on preference...a front-facing multifunction port panel.  These panels feature solid state media readers for things like digital cameras and video recorders, USB ports for extra peripherals like mice, direct connections for digital cameras, or external hard disks for backup (a good idea but let's deal with building the core system first).  The FP-01 comes with a variety of ports, but do some homework...try to do what you want with less space and fewer $$$.  You might find cheaper alternatives.

Next instructional post...how to put the thing together.

No comments:

Post a Comment