2.0 Laptop and Portable Devices
2.1 Identify the fundamental principles of using laptops and
The main difference
between laptop and desktop processors is the clock frequency and the power
consumption. Desktop processors are optimized for higher performance at the cost
of large heat production and space. On contrast, laptop processors are optimized
for smaller energy requirements (in turn improving battery backup time) at the
cost of lower clock frequency. Higher performance versions are also available
for laptops that consume more power. The disadvantage of using higher
performance processors (with large wattage requirements) is large heat
production, and smaller battery backup time.
Laptop processors typically use a surface-mount
Micro-FCBGA (Flip Chip Ball
Grid Array), or slot-mount form factor, while desktop processors use a
socket-mount form factor. The main advantage is smaller space requirement. If
mounted using FCBGA, the processor replacement requires special tools.
Various types of mobile laptop processors are briefly discussed
Core 2 Duo (Merom):
Core Duo is successor to Core Solo offering 5-20% more speed. The Core 2 Duo
for laptops is identical to the desktop Cure 2 Duo processors but the
notebook-processors work at lower Frontside bus clock (1066 vs 667 MHz). The
performance is 20-25% lower than Desktop PCs because of the lower Frontside bus
clock and the slower hard disks.
The energy need of the processors is marked by pre-set letters in front of
the type designation (number).
E ... 55-75 Watts
T ... 25-55 Watts (standard version in notebooks)
L ... 15-25 Watts (low voltage)
U ... <15 Watts (ultra low voltage)
Intel Core Duo
After first benchmarks the Core Duo completes all tests at least just as fast
as a equivalent Pentium M. With applications, which were designed for
multi-processors, the performance can be nearly twice as fast as with the
Pentium M (e.g. CineBench around 86% fast)
Pentium Dual Core T2060: 1.6 GHz, FSB 533 MHz, 1 MB L2 Cache (the return of
the name Pentium, though Yonah core)
Pentium Dual Core T2080: 1.73 GHz, FSB 533 MHz, 1 MB L2 Cache
Intel Core Solo
Single core version of the Core Duo and successor of the Intel Pentium M. The
performance is comparable with the equivalent clocked Pentium M (somewhat faster
because of a few improvements).
A typical T1200 model works at 1.5GHz, with 667MHz
FSB, and 2MB L2 Cache. A
ultra low voltage model (example U1500) consumes only 5.5 watts of power.
Intel Mobile Pentium 4
Recent Pentium 4 M processors operate at 2.4 - 3.46 Ghz (earlier versions
starting from 1.4 Ghz) with FSB 533 MHz (earlier versions offering 400) and
512KB to 1 MB level 2 Cache.
AMD Turion64 X2
64 bit dual core processor, code name Taylor (2 x 256 KB L2) and Trinidad (2
x 512 KB L2) offer DDR2-667 support, 31-35 W TDP, socket S1, 90 nm
fabrication, and separated L2 Caches. Typical specifications for TL-66 are
2.3GHz clock, 2X512KB L2 cache, and 35 Watt power consumption.
AMD Turion 64
This is a derivative of the Athlon 64 with 32 and 64 bit support, integrated
memory controller for PC3200 memory, 2 variants ML with 35 Watt and MB
with 25 Watt consumption.
AMD Mobile Athlon 64
Ghz) - 4000+ (2,6 Ghz). The rating is comparable with the clock
rates of Pentium 4 M. It is a 32 and 64 bit processor relative fast per
megahertz and uses moderately much current (and produces heat). The top versions
are DTR (Desktop replacement) versions for large laptops.
AMD Mobile Sempron
2800+ to 3000+ mobile Athlon 64 with reduced level 2 Cache; The rating is not
comparable with Athlon 64 Rating. A 3000+ Athlon 64 is faster than a 3000+
Sempron. There is no 64 bit support.
AMD Mobile Athlon XP-M
Mobile version of the Athlon XP is comparable with Pentium 4, and somewhat
slower than Athlon 64 with same rating and no 64 bit support.
refers to slowing down of the processor when required. For example, if you want
to conserve battery power in a laptop, you may want to slow down the CPU clock
to reduce power consumed by the CPU, and thereby increasing the batter usage
time. CPU throttling is also used to prevent overheating of the CPU.
Notebook Operating Systems (predominantly Windows XP) offers several options
to manage the power consumed by a laptop. The available options depends on the
exact hardware configuration of the notebook.
To open Power Options (XP) in your laptop, go to Start > Control
Panel > Performance and Maintenance > Power Options. Sometimes, it may be
slightly different in your laptop, depending on the OEM version of the XP
Power Options in Windows XP allow you to control the power management
The wireless local area networks
(WLAN) use radio waves for providing a
secure and reliable connectivity. It is based on IEEE 802.11 standard, and
operates in the unlicensed 2.4GHz and 5GHz radio bands, or both of them (dual
band), depending on the data rate your wireless hardware is using. There are
several specifications in the IEEE 802.11 standard family and new ones are
occasionally added, although all of them use the Ethernet protocol and CSMA/CA
(Carrier Sense Multiple Access with Collision Avoidance).
A WiFi (Wireless LAN) adapter may also be attached externally using USB port.
A USB WiFi adapter uses USB port for this purpose.
Basic Wireless LAN configuration consists of the following:
The name of the wireless local area network (called
Wireless working mode (infrastructure or ad-hoc, see below)
WEP key (for data encryption, only if necessary)
Two most commonly used wireless LAN configurations are given below:
Ad-hoc mode: Wi-Fi adapters on every machine using to the same WLAN make
connections with every remote machine. This configuration is suitable for small
Wi-Fi adapters on every machine using the same WLAN connects to the same
access point, which in-turn links all the remote machines into one network.