Wednesday, February 22, 2006

Ten Points every Beginner should know when buying a laptop.



Various aspects can decide what equipment is better for you, and this tutorial will try to cover, and hopefully it will, what you should know to understand some basics of the experience that is to buy a notebook. Its goal is to be a "what to ask" guide, so if this avoid one single question like the ones presented right below, this text fulfilled its objective.
Start by not asking anyone "what computer should I buy", "help me find the perfect laptop" or other generic variation like "help me find the perfect laptop for me", don't giving any clue about what kind of notebook you need. This is the mantra you must follow. I hope everyone will be polite to you when you ask that, but when you do you are just wasting your and other's time. As everything in your life, be objective. That's why this kind of tutorial is so much appreciated on forums, specially if you consider that most of the active users are here not to ask questions, but mostly to discuss and answer yours. It's very common to see simple questions turning themselves into a valuable resource because experienced users started discussing very pertinent arguments that end by improving the quality of the threads here, or in other forums as well.

When asking for suggestions, don't ask like that, beeing generic. Instead, tell what kind of computer you need, how much money you think you need to - and can - spend and if performance is important or not for you. Beeing simple: tell as much things as you can that help us to narrow the spectrum of possible computer systems that you would probably be interested in.

These tutorials save time, and here on notebookforums you can find lots of external links that can further extend your research (see some on the end of this tutorial). So, do your "homework" before anything.
  1. Processor

    Chances are high that you already know at least the basics of processor performance. Forget the clock speed (those "my computer has more megahertz/gigahertz than yours"). You can't trust only on that factor anymore. Today, other things like size of the L2 cache, the architecture, the data size and all that can change processors performance. The clock is not the only factor to consider anymore, like it used to be some years ago.

    There are processors that can handle data at 64 bits, for example. 32 bits processors can't process 64 bits, but "32 bits capable" 64 bits processor can process the other way. There are very good mobile processors from Intel and AMD today (as of late 2005), but if you want 64 bits, you will only find these beeing offered by AMD.

    Although 32 bits processors like the Pentium M are probably enough today, remember that this is going to change in the near future. However, it's not easy to guess exactly when it will be the default environment on the computer scene. Be aware that most people paid more to buy 64 bits processors in the past. While most of them had (and will have) benefits with 64 bits computing, others are already ordering other notebooks (or even desktops, for that matter). Finally, it's not hard to conclude that they paid more in the past without having a great - if any - advantage with those processors. The best buyer is not the first one to buy a given technology, it's the one that do it in the right moment.

    You can find suitable, mobile processors of both types today. So, you will have, mainly, AMD and Intel processors to choose from when buying. However, you can still find specialized processors with specific goals. Be sure to choose one that will fit your needs.

  2. RAM Memory

    This is the most important overall upgrade on your computer. The one that will most change your performance, financially speaking. There are some aspects of it that you must understand to get most of your money:

    1. Size

      More RAM memory can make your computer better when multi-processing, meaning that your computer won't access your hard-disk so much, increasing the productivity of your computer (decreasing the total time nedded to do a given task or group of tasks).

      More RAM also helps your computer to run more stable and flawlessly. Windows XP requires, at least, 128 MB, officialy, and the next version of Windows, called Vista, will require, at least, 512 MB to have a "good overall" performance (even if it can run with less than that), according to Microsoft. You can find notebooks beeing reselled with even 256 MB. So, you should get nothing less than 512 MB, specially when you consider that you can find most people with one year old notebooks with 1 GB or RAM.

    2. Speed


      You must, too, consider the speed of the memory modules, as long as it's supported by the system and as long as it - the system - will use the "extra clock speed". So, adding faster memory won't make your computer necessarily faster. The best buyer does not focus on only one component, but on all of them, balancing the performance among the system. Only this way you avoid bottlenecks, as a single, poor piece of hardware can ruin all those last model processors and graphic cards. Remember: it doesn't matter if you have that Ferrari. If you tune it wrong, a good Mustang will crush it.

      There are several kinds of SDRAM modules (the most used today). They are represented by the letters "PC" plus a number, as "PC2100", "PC2700", "PC3200", "PC4000 and so on.... If you can, choose the memory with the higher clock, specially because if you buy a brand new system now, probably it supports, at least, PC3200 memory models. Don't be confused when you find a memory described as either DDR400 or PC3200. The first scheme describes the maximum clock that the memory supports (400 Mhz, in our example), and the second one describes the maximum data transfer rate (in our example: 3,200,000,000 bytes per second, or roughly 3.2 GB/s). So, you can find DDR266/PC2100, DDR333/PC2700, DDR400/PC3200 and such.

      You must be wondering where this relation and the numbers come from. You can get the maximum data transfer rate of a memory by multiplying the clock cycles by the bus size. DDR SDRAM memories have a bus that is 8 bytes wide. So, if it can retrieve 8 bytes at each clock cycle, and it can perform 400,000,000 cycles each second (400 Mhz), it can send out 3,200,000,000 bytes every second. Fairly simple, isn't? That's why a DDR400 is the same of PC3200 and a DDR333 is the same of a PC2700. It's just a matter of names.

    3. Temporization or Latency

      Another thing that can affect the performance of your system significantly. The temporization, or latency, of the memory. Depending on what you do and who you are, you may don't even know a single person that knows what temporization is.

      The latency of the memory is the time (measured in clock cycles) that the memory module takes to complete one operation.

      Think of a scenario: you have two groups of people to extinguish a fire with buckets. What group of people would you choose? The one having very strong, gim-addicted people with one old, very weak person; or one with not so strong people, but all of them beeing definitely stronger than our old man on the first group? Exactly the same happens with computers. Consider two facts: CPUs today are faster than memory modules. The CPU need to wait the memory to access its stored contents for that same CPU to process the data retrieved. Read this carefully and it's not hard to guess that a memory module with high latency will make your precious (read: expensive) CPU not critical to your system performance as you once thought. Beeing simple, a high latency memory will leave your CPU "waiting" a lot of time before it can process any information.

      As said before, and it's doesn't hurt to put emphasis on it, the best buyer does not focus on only one component, but on all of them, balancing the performance among the system.

      The temporization is an array of 5 items, as X-Y-Z-W-V. Actually, for us to understand it better, we must write it as tCAS-tRCD-tRP-tRAS-CR. They are, respectively, Column Address Strobe delay, Row Address to Column Address delay, Row Precharge, Row Address Strobe delay and Command Rate. These numbers describe the amount of time the memory takes to perform different routines needed when dealing with the memory array. All the time is measured using front side bus clock cycles, so you will find 2-3-3-5 and simmilar variants. Note that the fifth element was not present, and you won't find it explicitely expressed often (normally, only the four first). Anyway, the Command Rate value is important to the system performance, so you should always ask for those when buying a memory, if possible.

  3. Video Card

    Also known as, but not limited to, "Graphics Card", "Graphics Processor Unit" or just "GPU", this component is, specially for gamers, one of the first considerations when buying a new computer/notebook. The video card renders the images that you see on your screen, and it appear in two form factors:

    1. Integrated Graphics:

      This kind of video card is, as the name says, integrated to the mainboard and usually doesn't have dedicated memory (or can have part dedicated and part shared). Besides the fact that this kind of video card normally doesn't have great performance and can't render graphics even like some of the cheapest "non-shared video cards", the fact that the card shares memory with the main memory of the system (RAM) just slows down things even more.

      Any GPU can handle (some times just not flawlessly) operations like Photoshop editions and simple CAD graphics. So, they are useful for two kinds of people: those on a budget, that can't afford dedicated graphic cards; and mobile users, since integrated video units are smaller and less powerful, thus requiring less cooling and placement solutions like heatsinks and space, beeing ideal for small chassis.

    2. Dedicated graphics:

      This kind have its own processor. They make all the heavy-duty of rendering graphics alone and don't use system's memory, increasing the overall system's performance.

      If you don't mind the money spent, you will be amazed by how much better graphics can be rendered with these cards. Photoshop and other relatively simple renderings when did on these cards are a pleasure to do, and any gamer considers this not just a must have, but they also will go for the lastest (or so) generation of these.

      What mostly determines the performance of the card is the processor unit for the video card. Actually, a video card is essentially a computer in itself, with a processor and memory. You can find a lot of cards with a given amount of memory, but the performance difference between them can be abysmal, depending on what is the processor on it. Choose wisely.

  4. Hard Disk

    Hard disk, also known as "winchester" by the old school, or just "HD", is the device that keeps your data permanently. Today's hard disks' capacities offer much more than the average user needs. They have plenty of space and, if you choose right, probably you won't run out of space, unless you need to process a lot of data, like what happens when you make professional conversions of VHS to DVD, or if you store a lot of multimedia files, like videos and high bitrate (higher quality) musics, on it.

    1. Capacity

      The main question at this point is how much things (and how big they are) you keep saved on your computer. 30 GB can represent plenty of storage to most people that only uses one operational system and those whose main usage is surfing the net and listening to some MP3s. If you play some light or old games, keep some videos saved and like having some free space for, who knows, try that Linux distribution that everyone is talking about, you want a minimum of 60 GB. However, if you are the storage man, who keeps all your albums on your hard disk to listen, deal with videos and uses more than one operational system, even 80 or 100 GB can run out of space quickly.

      You probably want to consider, in certain circunstances, an external storage solution, since it's not difficult to buy 3.5" hard disks, suitable for desktops, and put them inside enclosures. Doing that, you will probably save a lot of money than buying comparable internal storage for your notebook, as this difference can be, for simmilar capacities, something between 2 to 3 times the amount paid for a 3.5" hard disk on a good enclosure. And, by that, you must remember that most capacities won't even be available in a form factor that is suitable for notebooks, as the 2.5" is.

    2. Speed

      The speed that your hard disk spins gives you an idea of how fast you can read data from it. Although 10,000 RPM are quite common on the desktop world, you are more limited when dealing with notebooks. If you don't mind to wait a few more seconds each time you read a great file, you can choose one with 5,400 rpm (those around 4,000 rpm are becoming slow and obsolete). But if you need high performance, meaning less boot time and less "Loading" screens, settle for 7,200 rpm or more, if you can. However, be prepared to not just increase your computer's performance, but to increase the amount of money you will spend.

      Another factor that reflects how fast you can load things from them is the capacity (resulting from the higher density). Since a higher capacity disk keeps more data, the information stored on those disks are closer to each other, meaning that the disk is more dense than one with less capacity. Since the drive will waste less time to go from one point of information to another, you can say that higher capacity disks can load things proportionally faster to the density participation in the read process (keeping in mind that the density is not the only factor that determines the speed when retrieving information) if compared to a less capacity one at same speed.

  5. Media

    Almost nobody uses floppy disks today. Their 1.44mb capacity is obsolete for years now. Unless you have a very good reason, you can choose a notebook without such drive, saving money. It's even rare to find a notebook with an internal drive today, but there is still the option for externals. Anyway, remember that most companies will sell external floppy drives well overpriced, so you can save money by buying internal drives and external enclosures. After all, you are paying more only for someone to connect the drive on an enclosure with screws, which is, at most, a 1 minute task.

    Much more important than floppies are optical media. Almost every computer today comes with a standard CD-RW/DVD-ROM drive, but in almost every situation, you will find the option for a DVD burner. From some resellers, you can even have only DVD burners, as these are becoming the standard. Since the price of 2.5" DVD burners is dropping, buying external ones is not a great solution as it used to be, unless you need to use the same burner on different computers. Also, all new DVD burner models today have the ability to write to dual layer media, so it's not too important to pay attention to that, unless you are buying an older model.

  6. Screen

    It can appear a simple detail, as you should think that all screens are almost the same, since they just display what you're doing. You couldn't be more wrong. Resolution (both pixels and pixels per inch), aspect, viewing angles and the very own screen quality are subtle details that nobody can forget.

    1. Resolution:

      The LCD screen on your notebook will have a given number of individual points, and it's important to know how much points it have on both horizontal and vertical directions. Every screen today has at least 1024 pixels on the horizontal and 768 pixels on vertical. This resolution is known as 1024x768 or just XGA. As you can see, an XGA screen can display an image using 786,432 points simultaneously. And the more points you have, more things you can display on a screen at once. For example, icons are normally an image of 32x32 pixels. A screen of 64x64 pixels can display 4 icons at a time, and another one of 128x128 can display 16 icons at a time, just to compare.

      Another detail of the screen is the "pixels per inch" (a.k.a. "dots per inch", or just DPI). Given the size of a screen, which is measured on its diagonal (a 15" screen has fifteen inches if you measure its in the diagonal axis), and the amount of pixels, you have the DPI of your screen. Normally, a screen has a DPI number of 80 to 110.

      You are probably wondering: how the DPI number can affect my computer experience? Did you ever noticed, specially on those common and bulky desktop monitors (CRTs) that, when you change the resolution, the things on your screen gets bigger (or smaller)? That happens because more or less information is supposed to be displayed on that screen, but the real size doesn't change (obviously you can't increase the monitor size). For instance, if you increase the resolution (go from 800x600 - SVGA - to 1024x768 - XGA), more things can displayed at a time on your screen, but since your monitor itself doesn't get bigger, all the image needs to be "shrinked" to fit on the screen. That's the DPI effect on your life.

      The ratio between the amount of pixels and the size in whom they are displayed gives the DPI. Higher numbers means that things will be, in proportion to your screen, smaller; and low numbers, bigger. You don't need to understand this completely, but certainly, it's useful.

    2. Aspect:

      The proportion between the horizontal and vertical sizes of your screen gives you the "aspect ratio". Those "boxed", common screens, are defined as 4:3 (4 units at horizontal and 3 at vertical), while the "new wave" of home entertainment screens are defined as 16:9, wisely marketed as "widescreens". 16:9 screens (you'll find "16:10" on almost all wide notebooks) are better because they represent the image more naturally, with the same aspect of your eyes. However, personal preference is imperative here, so choose what you like.

      "Widescreens" can also display those DVDs you have at home using all the screen, which doesn't happen with "Standard" screen, where the movie is displayed shrinked to fit or distorted.

    3. Viewing angles:

      LCDs (specially cheaper ones) have a common problem: if you don't sit exactly in front of the screen - "perfect spot" -, you will see images with some kind of distortion (normally brightness and/or color). Better LCDs have greater "viewing angles", which means that you can sit in a great "angle difference" in comparision to the perpendicular imaginary line that gets out of the middle of the screen. Putting it simple, if your screen has "limited" viewing angles, you probably need to sit exactly in front of it to see images correctly.

    4. Dead pixels:

      Not everything on a new computer is paradise, as most not-aware users will be shocked. From such expensive items, you don't expect to get a defective system in any way, but when talking about screens, it's different. I won't discuss the very basics of image formation, but you must know that the image on a computer is rendered by points (lots of!) on your screen, each one with its color. They are so tiny and so close one with other that your brain gives you the idea that it's a "real image"..

      But, resuming the main subject, a defective pixel occur when one of those points is stucked on one color or just doesn't work at all. A defective pixel is quite easy to spot on lower resolutions, but more difficult on higher ones, like UXGA.

      It's very easy to check for them. Create a picture with the same - or bigger - size of your screen resolotution and paint it using just one color (strong, warm colors are usually best, and more used, for this task). Display this image on full-screen and if there is a defective one, you'll probably notice. When changing the colors, the pixel will be stucked on one color, and won't change.

      The bad news about defective pixels is that almost every reseller can ship to you a screen with a certain amount of dead pixels, and it won't be considered a defect on the product... others just charge to send a "No Dead Pixel" screen. Make sure to check your reseller terms about dead pixels when buying a notebook, or even a standalone LCD screen, because the same points apply for those, too.

    5. Glossy (reflective) screens:

      Glossy screens are a different kind of the normal, matte ones. It has a reflective appearance that will make the image on the screen to appear more crisp. Personal preference is also a big factor to consider here. However, glossy screens help eliminate the "screen door" effect, which consists on the black spaces between pixels (just look close to the screen to detect this).

    6. Response time:

      Since you can not choose freely (sometimes, just not at all) the screen on your notebook, this may not be useful for this guide, but it will be addressed anyway, for its importance to determine your computer experience. The response time is measured in milliseconds, and represents the time taken by a pixel to oscillate from fully active to fully inactive and then return to fully active (black-white-black). There is a lot of confusion regarding this, specially because, as many already know, pixels will stay most of the times between shades of gray, and not either black or white, and switching between shades of gray is slower than the previous scenario, which is the ones that manufacturers use and thus, normally, tell the fastest response rate, and not the average you will see in your daily activities.

      Slow response times will degrade image quality, specially on moving elements in the image on your screen. So, if you have an image moving faster than how your monitor can display it, you will detect and effect called "ghosting".

    7. Backlighting

      The LCD needs a light behind the screen to iluminate it, and the brightness control on your notebook or standalone screen will dim or not this light. One of the problems related to backlight is specially noticed with completely black screens. "Light leakage" is one of the terms when talking to the problem caused by uneven ilumination on the panel. Normally, this bad effect is noticed on the bottom of the screen.

  7. Mobility

    This is something that will be completely ignored by some, but can be well considered the main factor of decision by most people. Executives, outdoor technicians and all kind of mobile people knows what is beeing explained here. If you travel a lot and/or need to stay away from an electrical outlet, you probably are interested on these factors:

    1. Battery life:

      To achieve great battery life, a notebook needs to be designed to consume less power, so you can stay away from an electrical outlet for a long period of time. Processors will be the main component to look at when deciding about power consumption. The screen, while drawing a lot of power, is not a deal breaker here, since you can't control much what kind of it you will get on your notebook, unless you buy your equipment solely considering screen quality and power consumption, but this last information is not widely available.

    2. Weight:

      If you carry your notebook a lot, consider giving up performance and getting a light notebook. There are lots of notebooks below 4 lbs, and due to the size of the components, it's impossible to put a high-performance system on a 3 or 4 lbs chassis. If you buy a very light notebook (12" screen and so), expect less battery life than mobile 15", for example, since the battery size needs to be reduced to fit on such small chassis.

      Needless to say, there are very small notebooks as well, with screens sizes below 10" and 8". These computers are true hybrids between notebooks and PDAs, and certainly have their advantages.

      Remember that if you want raw performance instead of a light notebook that lasts a couple of hours using standard batteries, you probably want to buy a desktop replacement (DTR) model, with powerful, yet power-hungry, components.

    3. "Tablet shaped" computers:

      Those computers are specially designed for all the people who need a very portable system and need to make handwritten annotations. They are situated in the transition point between PDAs and common notebooks, but closer to the last ones, since they can act as a fully functional PCs, with performance more simmilar to these.

      Since they need to be light to be carried and will be in contact with your skin more often, they must dissipate a little amount of heat to not burn you, thus the hardware performance is limited. Normally, you will, from those systems, expect low voltage, mobile processors that improves battery life, and integrated graphics card, since they don't require all the cooling that most dedicated ones need. Besides that, most tablet PCs can act as an external monitor, too, which can be useful at some occasions.

      There are three types of tablet PCs: slate, convertible and hybrid. The slate kind doesn't have a keyboard, but you can use an external one with most of them. It is the closest "cousin" of the PDA that you'll find. The convertible, however, has a keyboard, like common notebooks, and its screen can turn 180ยบ, then folding to "convert" it to a slate tablet PC. It's perhaps the most common kind. Along, there is the hybrid type, which has a keyboard, like the convertible, but you can detach to use as a slate.

  8. Networking

    There are three common available types of Ethernet connection (commonly associated with wired networks, but they're not the same thing), different mainly about speed. They are 10mbps, 100mbps "Fast Ethernet" and 1000mbps "Gigabit Ethernet". Most notebooks will come with a network card that supports both 10mbps and 100mbps, and that's probably much more than what you'll be using for a long time from now, even if you find a notebook with Gigabit Ethernet capable card. Those that only supports 10mbps speed transmission are practically inexistent.

    You can, today, find not just the various wired ports on your notebook, but you have wireless options, too. With wireless networking, you can connect through eletromagnetic waves to a specific hardware, which is normally a wireless router connected through wires to your existent network or cable/DSL modem. Don't think you'll connect to the internet (or any private or public network, for that matter) by an act of God. You still need a specific hardware at the other "side", accepting your wireless connections. There are different protocols used, and the most common is the 802.11 standard, which can transmit data at 11 mbps, on the 802.11b standard; or 54 mbps is 802.11g and 802.11a. Watch out: it works through "waves", so they are susceptible to interference from cell/cordless phones.

    There are other protocols used, like Infrared, commonly used in older cell phones; and Bluetooth, present specially in portable devices and wireless hardware, as well as new cell phones.

  9. Features

    You should consider other factor when buying your notebook. Different manufacturers put flash memory readers (be sure to buy the same standard you use), Firewire connections (a.k.a. "iLink" or "1394"), USB ports (how much of them depends mainly on the notebook's size) using the USB 2.0 standard. Even ECP (printer) and serial ports can be absent, which seems ilogical on a desktop. Be sure to fit your needs.

  10. Payment

    The most important item. Don’t think you need to pay all your savings to buy a notebook. If you don’t know, you can buy a very good computer for much less than simple Sonys and Toshibas that costs much more! And the quality is still the same or better in most cases. Search the internet for more info. Or, even better, ask the Oracle.

    If the page you're buying is safe (have good encryption), you probably need to consider the Credit Card payment, and not instant cash or checks, specially if you don't trust that much on the reseller. If anything goes wrong, you can dispute the charge, and for sure the Visa or MasterCard name carries more influence than yours.

Remember! Ask the Oracle before asking questions to us. She has all the answers, and it's useless for us try to dispute with her and all her knowledge. It's also valuable to remember that your question can be very common, so it may had been answered before. That said, use the "Search" option, on the top of all pages on this forum, as often as possible.

Finally, all this work took some guesses, which means that this may not necessarily fit your needs.

You may ask questions now . However, if you want to know more, I highly recommend this other guide, provided by one very knowledgeable user here (smilepak). It can be useful as both a continuation to this one or as a first read. Enjoy.

Guide mostly based on advices given by the notebookforums.com users. Thanks specially to:

Tourney2112, kronus, Unleaded, abf, drawmonster, zlatanov, Aikeo, compujas, Sharakkhal, a13antichrist, Schmohey (some of them don't seem to be active anymore); and all of you who has been answering and asking questions in this last year and half.

Also all others that my slow hard disk (a.k.a. mind) can't remember now.

David Cesarino de Sousa (davidcesarino |at| |my-server-is-hotmail-ok?| |dot| com)
August, 23rd 2004

Revision: January 20th, 2006.

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