Hardware: What parts do what and how to troubleshoot them

[Firewing1]

Hey,

I've compared all the parts to our human ones -- I don't know why, but I find it's easier to understand that way...

Well, enough talking, let's get started!

Processors / CPU

The CPU (Central Processing Unit), or the processor is like the brain of your computer - It does all the calculations, like our thinking. It takes instructions (basic math like +, -, *, / or moving data) and executes them one by one. The speed that it can do so is called it's clock speed.

This clock speed is measured in hertz, although clock speeds are very high you'll only hear of MHz (mega-hertz, equivalent to one million hertz) or GHz (giga-hertz, equivalent to a billion hertz). 1 GHz = 1000 MHz. So, for example, your common new Dell at 3GHz is capable of 3 billion instructions per second. That's FAST thinking!

To be honest, I've never heard of a defective processor! It's rare (unless you overclock) to blow your processor. Either way, if you end up with a shorted one you'll know as your computer won't work!

You may or may not have heard about dual/quad core - The new Intel-Macs among others use the technology. Dell has a nice visual explanation of it here (Click the Side-By-Side tab).

When a processor has two cores, it's truly doing two things at once. This is real multi-tasking. In a single-core computer, since there is only one core, the computer can only do one thing at once. You might ask then why listening to music and browsing the web works? The processor still only does one thing at a time, but switches between your two tasks so quickly to the user it's seamless. But try burning a DVD and playing a game at once - You'll soon find out the computer has trouble doing both tasks at once since it takes a little of one, a little of the other, so on. In a dual/quad-core (let's group them into multi-core) setups, the computer actually takes two streams of instructions and does them at once. So using the same example - One core would take care of your game and the other your DVD - It's much faster that way than switching back and forth. You can see this article for more information, it also explains more in-depth why the difference between AMD an Intel's processors.

RAM (Random Access Memory)

Random Access Memory, or RAM, is temporary memory used by the computer. to keep things at a minimum, when you run a program, it gets loaded into your RAM and runs off there. When you are working on a document you haven't saved yet, it's in the RAM. RAM is for temporary things that need to change frequently. It makes sense seeing as it's at least 1,000,000 times faster than a hard drive!

As far as RAM problems go - If you're frequently seeing applications quit unexpectedly, seeing "segfaults" (segmentations faults) in Linux, or just having lots and lots of glitches, you might want to check your RAM for defects. You can do so with a nice piece of software called memtest86++. The easiest way to grab it is to boot from the Fedora Install CD 1 (or DVD) and at the boot prompt, type:

memtest86

NOTE: It will run forever! Keep a watch on it and if after a few times going through your entire memory no errors are present, <esc> (Escape) will restart your machine.

Graphics Cards

Graphics cards are what let the computer display an image to your screen, similar to the center of vision in the brain. There are two main types: Integrated cards and expansion cards.

Integrated ones are not as effective for 3D tasks, because they do not have as much circuitry as expansion cards do and they typically share memory with the system, which can be rather slow. Rather, if you are a gamer buying an expansion card will have a huge effect as expansion cards have their own processor (called a GPU, Graphics Processing Unit) and their own memory bank! This speeds things to a point where it allows 3D acceleration - essentially dramatically decreasing the visual lag of your gaming.

NOTE: Remember that before hardware (or 3D) acceleration will work, you need to install the ATi or nVidia drivers. (See my ATi and nVidia howtos for more info on how to do this)

Generally, if your screen is garbled, won't display things correctly, or something similar, it's a graphics card problem. Sometimes, replacing your card for an older one you have lying around (or buying a newer one if you have the cash ) will fix the issue.

There's no real rating for graphic cards per say unless you want to go deep and look at all the memory speed, GPU clock speed, and so forth. But, a quick and easy way to tell is by the memory size: A 128MB card is an average card; It will suit your basic gaming needs like Battlefield 2 at low quality, and it will easily run games like Warcraft III or Diablo at top quality. A 256 - 512MB card is considered high-end and will (easily in the case of 512) run games like Doom 3 and Battlefield 2 at a more decent quality.

SLI is another brand-new technology for vivid gamers: It consists of having 2 graphic cards (or even four of you have tons of cash to spend...) and then linking them together to form one immense one. Quad-SLI is a little bit of an overkill IMHO, but each to his/her own. (with Quad-SLI you can obtain up to 2GB of video memory -- that's 32x what I have on my system )

Hard Drives

Hard drives are the devices in your computer that allow you permanently save information on a computer, in effect the opposite of RAM.

They are a form of magnetic storage, so when something is written to a hard drive, it is converted bits (0's and 1's) and then into magnetic stripes on a big platter inside the hard drive. Because of this it can retain data permanent until erased or overwritten which is why you can save something and not have it erased when you shut down as would happen with RAM!

A hard drive's quality is judged by four main factors:[list][*]RPM (Rotations Per Minute)[*]Cache/Buffers[*]Transfer speeds[*]Capacity.

Rotations per minute and transfer speeds are fairly simple - The faster your hard drive spins, the faster it can read and write files, and therefore the greater the performance. The same goes for transfer speeds. The more your drive can take data in or put it out at a time, less Input/Output wait there is on the overall system, and the better the performance. A 7,200 RPM hard drive is standard these days, and 10,000 RPM hard drive is considered fast. For laptops, both 5400 or 7200 RPM are standard, although it seems we're slowly moving towards 7200.

Buffers, or cache, is also temporary memory. When writing something, a hard drive will take what it has to write from the RAM and store it into it's buffer - and as the buffer empties (stuff is written), more comes in from the RAM ensuring a constant supply of information with no waits or delays. The same does for reading: The as a hard drive reads, that data is put into the buffer and as it enters the RAM so the system can use it. Once the data reaches the RAM, it can be deleted from the buffer and be re-filled by the next thing to go into RAM.

So, in short, the more buffer memory you have, overall you'll notice smoother performance from you're hard drive when reading or writing files. Common sizes today for hard drive buffers or caches are 8 to 16 MB.

Storage space is measured in bytes, but again that's a very small measure and you'll mostly hear of 4 common ones:
KB (Kilo byte) = 1024 bytes
MB (Mega byte) = 1024 KB
GB (Giga byte) = 1024 MB
TB (Tera byte) = 1024 GB

For reference, your average MP3 song is about 4MB, average photo 1MB, a full 2-hour DVD is about 8 GB. A text file (Word document or OpenDocument) will only be a few KB.

Common problems with the hard drive may be a slow computer - this one's a mix. When your RAM is full but the computer still needs more, it uses what's called swap space on the hard drive. This works, but is extremely slow and because the hard drive is suddenly being constantly used, slows the system. Upgrading your RAM (adding more memory to your system) will solve this problem.

Other problems may be I/O (Input Output) errors, or read errors. These are the starting signs of a failing hard drive and if a reinstall of your OS doesn't solve it, I'd prepare for a hard drive fail.

If you want more information on hardware parts and what they do, wikipedia (en.wikipedia.org) will give you all the information you need.

(continued on my next post)

[Firewing1]

IDE Drives (DVD & CD drives)

As for CD and DVD drives, I've never really seen any problems in terms of support, so buy any one you want.

As for judging which one is a good drive, just like hard drives CD/DVD drives have buffers. I'm not really into this area, so I can't say what a "normal" buffer is for a CD/DVD drive, but I think it should be around 8 MB.

Another VERY important thing to look for, in fact the most important, is the drive speed. You'll see things like CD-RW: 48x. or DVD-RW-DL:8x. These are the drive speeds. 48x mean the speed of the drive is "48 times". The faster this rate is, the more your CD/DVD drive can read or write off a disk. Average for CD drives are 48x, and for DVDs it's 8x. Please also note that if your DVD and CD burner states 8x burning, don't worry. This is 8x DVD burning which is fast by today's standards and the CD burning will be extremely fast.

Wireless

A wireless card is a add-on card for your computer or laptop that enables wireless connections to the Internet.

I've never owned a personal laptop so I won't be able to tell you which chipsets are supported well in Linux, but I can say that Livna has both ndiswrapper and madwifi in their repositories, so most cards will work after installing these tools.

Motherboard

The motherboard is the part that connects all the different parts together - Hence, 'mother' board. Your CPU, RAM, and also all add-on cards are attached directly to the motherboard in slots, and your hard drives and CD/DVD drives get attached to the motherboard (commonly abbreviated 'mobo') via cables.

You should pick carefully and double-check the specs for your motherboard to make sure not only will it fit in your case but also that your RAM and CPU are compatible with it. Each motherboard has a socket type, and only certain CPUs are compatible with that socket. Also, you motherboard will only support certain types or RAM and certain speeds, so make sure that your RAM is compatible, too.

Power Supplies

Power supplies are, well, what supply power to your computer's motherboard and components. The only real way to rate a power source are by other's reviews and it's wattage.

The more devices you attach to your computer, the more power is drawn naturally. You have to have a power source strong enough to handle that draw or else your system will eventually fail. Standard today is 400W to 600W power sources, 400W being typical and 600W for gamers with many hard drives, fans and even SLI setups.

A nice tool I found that helped me find the wattage I needed for my new computer is the Power Supply Calculator at journeysystems.com.

Another thing to remember is to buy the right type - Make sure you're buying a ATX-compatible power source when you have a ATX case!

Cooling equipment

There's not really much to say here, but it's one of the most important aspects of your computer. Buying a good fan for your CPU and even another for the case to circulate air is always a good idea, even if it's an extra $50.


My favorite brands & online retailers

I don't want to drone on about this kind-of stuff, so I'll make it quick:
I'd like to make it clear that I am not sponsored or affiliated with the companies I mention in any way... This is just my opinion at the time of writing about the products on the market.

I've never "experienced" Newegg as I don't live in the U.S., but from what I hear this is _the_ place to order from.

If you live in Canada, I the multitudes of positive reviews I've read I can recommend NCIX and I recently ordered from Direct Canada and they have great prices and even better customer service.

As far as brands go, from reviews I've read, opinions on this forum and bits here and there I concluded that my favorite brands for cooling is Arctic Cooling. I think Thermaltake and Antec make good power sources and I've yet to see one of my Western Digital drives fail. I like to buy my GPUs from nVidia simply due to the fact that they seem to have less problems with Linux than ATi does, and finally Gigabyte and Asus are my preferred motherboard brands.

Oh, and if you looked here to find out about printers and Linux, I can recommend HP. They release HPLIP, a open-source driver project for HP printers and some scanners, too! I've never seen a HP printer be incompatible with my Linux install(s).

Still looking for more?

I recently was ordering parts to a new computer, and I wanted to make sure each product I was buying was going to last. Not only that, but I wanted to know which parts were better performing, etc. Comparisons. I found three sites that helped me choose my hardware:
- Tom's Hardware
- Newegg
- CNet reviews

Firewing1

[tomcat]

Other problems may be I/O (Input Output) errors, or read errors. These are the starting signs of a failing hard drive and if a reinstall of your OS doesn't solve it, I'd prepare for a hard drive fail.

This is not 100% correct. I have experienced read/write errors/ IO problems with several new Hitachi hdds and it was not due to failing hardware but due to a bug in the linux-kernel. Thus, if the harddrive reacts with DMA timeouts and I/O errors, you should download some diagnostic tools for the hdd from the hdd-producer and check the drive thoroughly. If no errors are reported by the diagnostic-tools, then there is a very high chance that there is a bug in the kernel. Now check bugzilla and submit a new bug if necesary.

PS: Sorry for hijacking this thread.

[Adesso]

I would love to hear some comments from you on other technologies, like Wireless, USB devices, Twain devices and perrefirals like tablets and joysticks.

Running a server with the suggestions above I would agree makes perfect sense, and is sound advice, but like most people out there I want a bit of entertainment too. What are the strong point hardware wise currently supported by Linux. Can I expect to use my Wireless Internet with touch screen LCD and play a flight sim on the net, or am I still going to have to dualboot into a windows envioroment for that.

Lets face it, Linux is not very easy to use yet, and for a new computer buyer, there are so many optional extra out there that they get. What are the things or brand that should be focused on.

So Far it is AMD cpu with any type of RAM, a Western Digital Hard Drive and nVidia video card. I am guessing that optical devices are also not problematic then, but what about the rest. Just try and buy a new system on the net right nor and see what you get. The real question is... is all that going to work in Fedora?

I relize that you can cover everything, so anything extra would be nice.

Thanks for the great info so Far

[sej7278]

AMD currently is ahead of the game on the processor front, although the low-end chips like the Sempron are crap.

OCZ is overclocker RAM, in fact it's all I buy these days. I refuse to buy Corsair because of all the bloody banner ads all over the internet!

On Linux, you really should go for NVidia graphics cards, in fact I don't like ATI much on Windows!

SATA drives have to be Western Digital. For IDE, Seagate are reliable, but loud, nice 5 year warranty though. Avoid Maxtor at all costs, Hitachi/IBM are almost as bad.

[tscheez]

just remember, harddrive manufacturers like to say that 1GB = 1,000MB and 1MB = 1,000KB to inflate the advertised space. eg my 250GB Maxtor is really 227GB

[pparks1]

low-end chips like the Sempron are crap.

I couldn't possibly disagree more with you about this statement. I have a Sempron 2800+ in my current Linux box at home and it performs beautifully. The choice of processor is really going to be determined by your needs. For example, if you need dual-cores and heavy gaming than you want to buy an AMD 64 X2 4200+ (about $360 at Newegg). But if you aren't using your Linux box for gaming, you can pick up a Sempron 3100+ for about $90. For most users at home on a Linux box, i'd be willing to bet the performance difference won't hardly be noticeable at all. So to classify a Sempron as crap because it doesn't meet your requirements isn't really fair.

[tomcat]

I second this. I have four machines running with the sempron processors. No problems at all. Fast, stable, silent, reliable.

[brunson]

Firewing, Thanks for another excellent piece of documentation. But I have to ask... when was the last time you went outside?

[brunson]

Oh, yeah, I disagree about the Sempron, too.

[brunson]

Can I expect to use my Wireless Internet with touch screen LCD and play a flight sim on the net, or am I still going to have to dualboot into a windows envioroment for that.

95% of people use a computer for nothing more than reading email, surfing the web and occasionally doing a little word processing.

You aren't going to get vendor support for esotheric hardware like touchscreens until Linux is more widespread, but by the same token, you're not going to get a stable, reliable, extensible, FREE operating system for running a server application from Redmond. But, then again, most people don't care about either.

[Firewing1]

Originally Posted by brunson

Firewing, Thanks for another excellent piece of documentation. But I have to ask... when was the last time you went outside?

Outside... What's outside?
Sorry about having it incomplete, I'm really busy and working on my other howots (and software - FWBackup's & audio-convert-mod's next versions are coming along slowly....), I'll try to get it done when I can... You're right though, almost all IDE drives are supported. I've had no trouble there, even when using VERY old computers.
EDIT: I added more info to hard drive and I also added a CD/DVD section
Firewing1

[Firewing1]

Originally Posted by Adesso

I would love to hear some comments from you on other technologies, like Wireless, USB devices, Twain devices and perrefirals like tablets and joysticks.

Wish granted: (long overdue) I spellchecked it and also added Wireless among other things...
Firewing1

[mwette]

Another approach to this topic is to have short descriptions ending with
links to Wikipedia. You will find gobs of information there.

[Adesso]

Thanks for the effort Firewing

The info is really good, and great if you live in Canada, but still good. I love the Watt calculator link, it gives you a good idea of how much you are consuming.

I would also like to add something about brand buying. Check the service first, before buying, or buy small to see what service they provide. No matter how good or bad it is, service makes the difference.