Laptop Computer Buying Guide

Buying Guide Glossary Compare

The Basics
While most users think of laptop computers as desktop computers you can carry around, that's not always the case. True, some laptops are designed as desktop replacements, offering similar power and performance on the go. But many laptops have other tricks up their sleeves, serving as tablet PCs or multimedia players in a fashion that their desk-chained brethren could never match.

But first, we'll talk about the similarities between laptop and desktop computers and what you should look for when you're shopping for a portable PC. Microsoft's new Windows Vista operating system came out this year, and it is available across the industry in new laptop computers. There are several variations of Vista, ranging from a Basic to an Ultimate Edition, but most laptop computers ship with either Vista Home Premium or Vista Business. These mid-range operating systems offer lots of multimedia tools and corporate features respectively, packaged in the sleek Aero interface with its translucent windows and Mac-like animations.

Any OS upgrade requires a little extra fire in the belly, and Vista is no exception. Luckily, laptop computing power continues to grow at a rate as fast--in some cases even faster--as their desktop counterparts. Most new laptop computers ship with dual-core processors, which are CPUs that pair two processing cores on a single chip. These processors speed up performance nicely, especially with more intensive applications and multitasking. Most of these processors are also 64-bit, which means that they can handle Vista to its fullest potential (the OS is available in both 32- and 64-bit versions) and are ready for upcoming applications. Dual-core, 64-bit processors are available from both AMD and Intel, so which version you want comes down to personal preference.

We'll talk about the rest of the components you might find in a laptop computer in our How to Shop section, but first, here are five questions you should consider before buying a laptop.

How Fingerprint Scanners Work

Computerized fingerprint scanners have been a mainstay of spy thrillers for decades, but up until recently, they were pretty exotic technology in the real world. In the past few years, however, scanners have started popping up all over the place -- in police stations, high-security buildings and even on PC keyboards. You can pick up a personal USB fingerprint scanner for less than $100, and just like that, your computer's guarded by high-tech biometrics. Instead of, or in addition to, a password, you need your distinctive print to gain access. In this article, we'll examine the secrets behind this exciting development in law enforcement and identity security. We'll also see how fingerprint scanner security systems stack up to conventional password and identity card systems, and find out how they can fail.

Why are there limits on CPU speed?

When you buy a CPU chip, it has a "maximum" speed rating stamped on the chip's case. For example, the chip might indicate that it is a 3-GHz part. This means that the chip will perform without error when executed at or below that speed within the chip's normal temperature parameters.
There are two things that limit a chip's speed:
Transmission delays on the chip
Heat build-up on the chip
Transmission delays occur in the wires that connect things together on a chip. The "wires" on a chip are incredibly small aluminum or copper strips etched onto the silicon. A chip is nothing more than a collection of transistors and wires that hook them together, and a transistor is nothing but an on/off switch. When a switch changes its state from on to off or off to on, it has to either charge up or drain the wire that connects the transistor to the next transistor down the line. Imagine that a transistor is currently "on." The wire it is driving is filled with electrons. When the switch changes to "off," it has to drain off those electrons, and that takes time. The bigger the wire, the longer it takes.

Introduction to How Motherboards Work

Motherboards tie everything in your computer together. Go inside motherboards with diagrams and video and learn about sockets, the CPU and computer.. the case off of a computer, you've seen the one piece of equipment that ties everything together -- the motherboard. A motherboard allows all the parts...
Computer
> Hardware Basics

Form Factor
From How Motherboards Work
Form factor is one of many standards that apply to motherboards. Learn how form factor and other standards affect how a motherboard looks and works... A motherboard by itself is useless, but a computer has to have one to operate. The motherboard's main job is to hold the computer's microprocessor...
Computer
> Hardware Basics

How RAM works?

How RAM works?

Types of RAM
The following are some common types of RAM:
SRAM: Static random access memory uses multiple transistors, typically four to six, for each memory cell but doesn't have a capacitor in each cell. It is used primarily for cache.
DRAM: Dynamic random access memory has memory cells with a paired transistor and capacitor requiring constant refreshing.
FPM DRAM: Fast page mode dynamic random access memory was the original form of DRAM. It waits through the entire process of locating a bit of data by column and row and then reading the bit before it starts on the next bit. Maximum transfer rate to L2 cache is approximately 176 MBps.
EDO DRAM: Extended data-out dynamic random access memory does not wait for all of the processing of the first bit before continuing to the next one. As soon as the address of the first bit is located, EDO DRAM begins looking for the next bit. It is about five percent faster than FPM. Maximum transfer rate to L2 cache is approximately 264 MBps.
SDRAM: Synchronous dynamic random access memory takes advantage of the burst mode concept to greatly improve performance. It does this by staying on the row containing the requested bit and moving rapidly through the columns, reading each bit as it goes. The idea is that most of the time the data needed by the CPU will be in sequence. SDRAM is about five percent faster than EDO RAM and is the most common form in desktops today. Maximum transfer rate to L2 cache is approximately 528 MBps.
DDR SDRAM: Double data rate synchronous dynamic RAM is just like SDRAM except that is has higher bandwidth, meaning greater speed. Maximum transfer rate to L2 cache is approximately 1,064 MBps (for DDR SDRAM 133 MHZ)

XDR™2 Memory vs. GDDR5

The Future of Memory

XDR™2 memory is the latest generation of the award-winning XDR memory architecture. Capable of unprecedented data rates of up to 12.8Gbps, XDR2 is the world's fastest memory solution. It delivers twice the peak bandwidth per device when compared to GDDR5 DRAM.

Fast and Smart

The XDR2 memory solution provides incredible bandwidth performance and does so at far lower power than GDDR5 memory. In fact, XDR2 consumes 30% less power than GDDR5 at equal bandwidth performance. Given equal power budget, XDR2 memory provides 50% more bandwidth than GDDR5. And at full speed, XDR2 DRAM deliver twice the bandwidth of GDDR5 devices.

Mobile Memory Initiative

Squeezing big performance into tiny packages

System-in-Package (SiP) technology stacks a number of integrated circuits - such as a media processor, DRAM, and Flash memory device - in a single package or module. SiP allows designers to achieve high functionality in a very compact space making it ideal for mobile phones. Though it offers great benefits, SiP faces a big challenge: the difficulty in determining whether memory devices are known good die (KGD) before assembly of the SiP. This can lead to poor manufacturing yields and increased costs. Thanks to Rambus innovations, available for licensing, technology such as SiPFLOW™ can address the KGD challenge achieving assembly yields of better than 100 defective parts per million devices (DPPM). That means designers can squeeze more performance into mobile phones at a price that consumers will like.

Graphics RAM GDDR5

Qimonda GDDR5 introduces features and functions that go beyond previous GDDR standards and enables today’s GDDR5 to operate at data rates up to 6 Gbps, three times the performance of todays high speed GDDR3. The GDDR5 combines highest performance with stable system operation and low implementation costs.

Memory bandwidth is a key factor in the rapidly increasing 3D rendering performance of PC graphics systems and game consoles. Over the last years, the memory bandwidth of graphics DRAMs grew by nearly 30% per year. Bandwidth of graphics memory systems exceeds those of PC main memory by far.

GDDR5 Benefits

• Highest bandwidth
• Robust signaling concept
• Low implementation costs
• Easy system bring up
• Fast time to market

XDR™2 Memory Architecture world's fastest memory system solution

XDR™2 Memory Architecture

The XDR™2 memory architecture is the world's fastest memory system solution capable of providing twice the peak bandwidth per device when compared to a GDDR5-based system. Further, the XDR2 memory architecture delivers this performance at 30% lower power than GDDR5 at equivalent bandwidth.

Designed for scalability, power efficiency and manufacturability, the XDR2 architecture is a complete memory solution ideally suited for high-performance gaming, graphics and multi-core compute applications.

Initial systems can achieve memory bandwidths of over 500GB/s into an SoC. Each XDR DRAM can deliver up to 38.4GB/s of peak bandwidth from a single, 4-byte-wide, 9.6Gbps XDR2 DRAM device, and the XDR2 architecture supports a roadmap to device bandwidths of over 50GB/s.

Capable of data rates of 6.4 to 12.8Gbps, the XDR2 architecture is the latest generation in the award-winning family of XDR products. With backwards compatibility to XDR DRAM, the XDR2 architecture is part of a continuously compatible roadmap, offering a path for both performance upgrades and system cost reductions.

USB Bluetooth Adapter, USB to Bluetooth Dongle, 10M Class 2

Product Description

Ultra

Portable! Plug & Play!

Bluetooth is popping up on mobile phones, PDAs, cameras, and even printers

these days, but what about your PC? Meritline tiny USB Bluetooth adapter plugs

into a PC's USB port so that it can interact wirelessly with other devices.

Bluetooth is not as fast as a 10/100 wired Ethernet or an 802.11b/g wireless

connection, but it's fast enough for synchronizing PDA data, transferring the

occasional file from PC to PC, and casual Web browsing.

By connecting your PC to a Bluetooth enabled mobile phone or PDA using

Meritline USB Bluetooth adapter you can:

• Connect your PC to a Bluetooth enabled mobile phone
• Connect to the Internet, send and receive email, browse the web
• Synchronize with a Bluetooth enabled PDA
• Hook up to an office network (with Bluetooth access point)
• Communicate with other Bluetooth devices

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