In here, we'll discuss upgrading computers, and what parts to get.
Feel free to comment on anything, and point out any flaws that I may have made while writing this.
Also wall of text.



So, you want to build yourself a new computer, but you don't know exactly what to do, or what brands to get.

Well, then you're pretty lucky that I happened to be bored at 1:30 AM, and wrote this thread.

Picking the brand and parts is pretty straight ahead. It's all about "Does it fit with this"
For example, PC3-12800 ram won't fit in your foxcon motherboard that only supports PC2-6400.
Selecting a brand is another story, which I'll come back to right after learning you about how to select the right parts.

~Selecting a case~
This is the easiest step, yet the one that can backfire the most.
It all comes down to a simple question, which type of computer are you planing to build?
Is it a media center, or a gamer pc?

These are the smaller motherboards, usally used for media centers:
Mini-ITX: Case - Motherboard
Micro-ATX: Case - Motherboard

Then there's the normal ATX size, and the different sizes of cases:
ATX: - Motherboard

The mid-tower;

You can recognize it on the fact that it has 4 CD-trays, which they usally have.
Everything seems to fit just barely in them. There's no extra space to be found in these cases, there's simply no mercy if you wanna have more than 2 hard drives, and a long graphic card aswell.
These are very common, and I bet we've all owned one at one point.

The big-tower;

These towers are massive. If you though the playstation 3 was huge, then let me tell you this. You can fit 5 PS3's with ease in one of these towers, and that's without removing the CD and HDD trace.
These give you that enormous workspace you want, and the infinity ammount of upgradeability with practically no limits on how much you can add to your computer.

There's also server cases, and rack mounted cases. B-ATX cases and all that, but I'm gonna focus mostly on the average computer we have under our desk.

Now that you know which case to get, let's move onto the motherboard.



~Selecting a motherboard~
This can be one of the hardest, or easiest parts of selecting the parts for your computer.
Some of you may want 2xPCI-E x16 ports for SLi/Crossfire, and some may want 3x PCI-E x1 for your TV tuners and audio cards.
To simplify it, all you want is to judge which parts you'll go with later on.
If you want AMD, you'll want an AM2+ or AM3 socket on that motherboard. If intel, you want a 1156 or 1366 socket (The 775 socket won't be worked on from now on, so no point in getting it)
To select which CPU you want, take a look at the money in your hand.
If you have over $600, pick a 1156 socket, if you have below, go with an AM3 or AM2+ socket, and if you have over $1000, then go to a 1366
Else than the socket, you'll wanna take a note of things such as the type of RAM it uses, and how many.
You'll want one that supports 8GB of ram or more, so you won't have to upgrade right away.
For a graphic card, you'll want a PCI-E x16, if it's 2.0 or not won't matter, but 2.0 will be the better option, as it has more bandwidth.

Just to explain to you what the different things I just mentioned is;
PCI is the old universal port from some year I can't remember and can't be bothered googling.
PCI-E is the express version, which is most used for Graphic cards, as they require a high load of bandwidth, whereas TV tuners doesn't require anything, and can practically run off a 30MB/s USB2.0 rather than a 60Gbit/s PCI-E port
1156, 1366 and AM2+ is the socket of a processor. Under a processor there's a lot of small golden pins. If the socket is right, the pins goes into small holes, if it's wrong, you bent them and ruin everything.


~Selecting a CPU~
After you've picked the motherboard, you most choose a matching CPU.
As I said earlier, if you have over $600 on your budget, you should've picked a 1156 socket, if you have less you should get an AM3 or AM2+ socket, and more than $1000 and you might aswell get a 1366 socket.
One of the most important aspects of selecting parts for a computer, is not to fanboy something. To get the best performance out of that money of yours, you'll in most cases have to go with different brands than you're used to.

For +$600 gaming I'd say get a i3 or i5 (depending on the budget), for -$600 gaming I'd say get a AMD Athlon II X2 240 Regor 2.8GHz
Why isn't there any i7's on the 1366 socket under my "gaming computers" list? It'simple.

Most games doesn't support more than 1 or 2 cores, and buying an i7 with 4 cores and HT (that's a total of 8 cores) just for gaming is pointless, as you won't be using 6 of them.
i7's are for people who do 3D rendering, or in general needs a lot of cores for CPU intense stuff.

I've choosen the i3, the i5 and the AM3 socket version of the Athlon because it's a highly clocked dual core, which is what you'll need for gaming, and as the games won't support more than 2 cores anyways, you want as much as possible to be able to pump through those 2 cores, so it won't suddenly stop working because you crashed your car and it needs to calculate the physics.

Picture to explain the differenses bethween the different sockets;


~Selecting RAM~
RAM is probably some of the easiest to select. It all depends on the motherboard, and your budget.
If you're planing on building a $500 budget computer so that you can play games such as WoW or HL2, you won't need more than 2GB of ram, whereas if you're thinking of cacheing the entire world of Crysis for instant loadtimes, or thinking of fully cacheing 4x DVD's to burn them all out at the same time, then you'll need as much as 12 gigs of RAM.

Now there's a little differense bethween ram, it's not all just temporary storage (well technically it is)
All ram is a type of ram. PC2-6400 ram is ram doing 800MHz or 6400MB/s. the 2 also tells us it's DDR2 ram, which has the feature of dual channel.
Dual channel basically does so that ram can send information to other ram a lot faster than normal DDR ram would.
Same goes to tri-channel, except now it's 3 blocks of ram.

When picking the ram, you most check if it also physically fits with the ram.
On the motherboard there's enough slots on the motherboard, to fit the many ram you've selected.
For example, 2x ram of any type, won't work with a pack of 4x ram of any type, as there'll only be able to be 2 connected at once.

You most also check if it digitally fits together. As mentioned above, all RAM runs at a certain speed.
If a motherboard supports up to 8GB of PC2-6400 ram, you'll have to find that kind of ram, or else it simply won't work, and can sometime even damage your hardware.



~Selecting a Graphic Card~
So you want the best of the best, and play crysis very high at 500 fps? Well this way is much more boring, yet requires me to type less text.
Basically you gather all the parts for your computer, and then you look at the remaining budget.
If you have $100 left, I'd say go with an ATi 5670, whereas if you have $400 left, you might aswell get a 5870
To find out if your selection is what you wanted, go to Tom's Hardware, and under the Charts section, you'll find a section for graphic cards. (There's also one for processors if you wanna check that aswell)
Pick the gaming charts 2009 (or just the newest avalible), pick a game, CTRL+F and search for your graphi card's model ID (example, Nvidia GTX275 then the model ID would be GTX275), and then you'll see how well it does compared to others.
You can also go and check manually if the better graphic cards are in your price range.
Remember though, paying $20 extra for 2FPS more isn't worth it. Paying $20 for a 20fps increase however, is exactly what you want.


~Selecting a Power Supply~
This is what will keep your gaming going, or prevent your daily fap to be interrupted.
It's the heart and soul of your computer, and if it blows then everything stops with it.
Buying a cheaper power supply can even result in everything dying with it, and then you'll have to rebuy everything.
There's a simple rule about power supplies, the more you pay the more sure you can be that it'll work.
I prefer these brands; Corsair, OCZ, Thermaltake, and Cooler master.
To find out how much power you'll need for your build, head over to corsair's website, as they've got this neat thing that'll tell you how much you'll need:
Welcome to Corsair


~Selecting a Hard Drive~
- Low price
- Speed
- Storage
Pick 2 out of the 3 above. It's that simple.
There's things you wanna notice though. If your motherboard supports SATA or it's so old it only supports IDE.
If your case has anymore free 3.5" slots, and if the hard drive you've selected is a 2.5" laptop hard drive.
To find a speedy one, you can once again head over to Tom's Hardware
Direct link to their hard drive tests:
Benchmarks 2009 3.5" Desktop Hard Drive Charts

There's also other things to know about hard drives, such as RAID.
RAID is a way to set up multiple hard drives to run with each others.
RAID0 basically splits the data in 2, putting half on each hard drive, meaning it gets an incredible boost in load times.
RAID1 mirrors the hard drive onto another hard drive automatically, which means if 1 of them dies, you just swap in a new one and it's all copyed over automatically as if nothing hat happened.



~Selecting an Optical drive~
This is one of the things you can cheap out on, and stick with your fanboyism.
Basically by using your DVD-Writer a lot, it'll only last a year or two, so either way, no matter how much you pay for it, it'll always die in a short ammount of time.
One thing though, I'd stay away from LG's cheaper DVD-Writers, as they've installed the most annoying firmware on them ever, which makes adverts pop in your face everytime you use it.



~Selecting the right brands~
Basically none of the brands make their own products. Maybe larger brands such as AMD and Intel, Nvidia and so on, they make their own brands, but ASUS doesn't make ATi graphic cards, and nor does BFG make Nvidia graphic cards.
It's all the same in the end, except for tiny details as which transistors they've used, and what memory chips they've decided to go with.

Basically for the majority of time, you can sound it on the brand name.
Afterall, would you want a "Konichiwa chingbong PC3-12800 2GB" RAM in your brand new $800 gamer PC? I know I wouldn't.

For the majority of times, you can just google their brand name.
If the first result is a website, then it's somewhat legit, however brands such as "Stability Power" that doesn't even have a website, is just something that you'll have a constant fear for killing you in your sleep.

Another thing you can do, is look it up on places such as google. Normally googling the name + review (Example: "Nvidia GTX285 review") gives you a couple of reviews of what you're looking for.
This works for almost everything. Graphic cards, Cases, Power supplies, and so on.

Now that you know everything there is to know about computers, I'm temporarily gonna say move on to

It's now 2:55 AM and I've just found out what a pointless wall of text I've just written.
Hope you'll find it of any use. Thanks from here, and goodnight.