Laptop Computers

In order to estimate time of the offline laptop computers work for the last years there are not so many tests. MobileMArk 2002, from one side, realizes in the scripts useful pauses, in which Intel Enhanced SpeedStep and AMD PowerNow technologies distinctly shows themselves, dynamical or adaptively, managing working processors' points "frequency- voltage". From the other side, in spite of that benchmark is built on the SYSmark 2002 base, it wasn't liked, because scripts of system load or workload and the calculation of productivity were very simplified, though theoretically SYSmark 2002 loads the system heavily than 2001. The package Business Winstone Battery Mark 2004 went out not long ago and we haven't time to test it and even then we have nothing to compare it with. Though, judging by the name, it is obvious, that there is no serious system load.

One more time we'll expound in details the matter of testing methodology TerraLAB and the indexes, which are entered and calculated by the estimation offline work. The base is the cyclic using of the tests in package SYSmark 2001 - Multimedia Content Creation and Office Productivity, one by one to full battery exhaustion, i.e. "dying" system. The warning about low charge and other spontaneous actions are providently switched. Test is used in different modes of processor productivity control, and - attention! - result will be not simply time, which is often brought as the main index, as for package MobileMark 2002,for instance. On principle you have better to take into account productivity, which laptop has demonstrated during this time.

The main observable value is the pair "productivity - time". It is not difficult to guess, that they are in back proportional dependence. It is possible to fix processor frequency on the maximum (and accordingly power voltage) and then we' receive the minimum time of the offline work. Fixing on minimum we' retrench maximum battery energy and gain the time. On automatic (adaptive) frequency choice we'll receive the third result. What mode is the most optimal? It seems, the answer is evident: we must long for maximum duration of mobile work. But it is not so easy. Just imagine, during the time of the flight you need to recode written during business trip video rolls, in order to prepare presentation. At processor economy the number of processed rolls will be cut, and it is not fact, that during less time, but with maximum frequency you'll process them less.

I'd like to accent, that in SYSmark 2001 it is imitated a man's behavior, who work at the keyboard, with pauses, placing and appropriate speed of input tasks, that allows modern processors retrench energy a little (for example, tests Winstone are not suitable, because they test with high speed). SYSscore index is calculated from the feedback time of system on the user's request and therefore is linear response to speed of command execution, i.e. shows productivity. Having multiply SYSscore result on time, during which given level of productivity was supported, we input the index, that characterizes autonomous calculating abilities of the concrete system. We call it autonomous calculating storage (or Workdone).

It is obvious, that autonomous calculating storage is linear response to accumulator capacity of laptop and the weight of the last, therefore for objective comparison in the capacity of additional parameter so called efficiency of configuration is calculated: calculated storage that refers to battery capacity and computer weight (you may refer all to the volume). How much economical laptop is in one or in the other mode you can determine due to calculated value, so called average consumed capacity, which is equal quotient from the division battery capacity on the offline work time.

We must understand that test of the systems on offline work time from the batteries only with using of resource-intensive scripts SYSmark 2001 was one-sided. We use also one simple test - DVD-Video playback that characterizes economy of the video accelerator and CD-R/RW drive. Productivity is not taken into account: modern mobile processors without problems cope with decoding MPEG-2 and Dolby Digital through software players, wasting less then 50 per cents of resources. In the capacity of DVD-film we use 18 GB (double-faced two-layer) disc "Aquaria" with recording about Aquarian fish life, which is programmed for more then 10 hours continuous demonstration. Almost on all systems that were able to reproduce independently DVD, Power DVD 4.0 was installed, the option of supporting hardware acceleration of replay with help of video card wasn't on. For most of laptop computers test is taken in the mode "Portable/laptop", the brightness of the screen is put on maximum, in some cases it is forcibly cast off by the system during the working from the battery (about 10-15 percents, and in some laptop computers you can't turn it off).

In conclusion we'll say about things that are less paid attention. First of all, they are the display characteristics: we do not take any precise measurements of speed, brightness and color rendition. It hasn't any sense, cause laptop computers producers can use today components from one plant, a tomorrow - from the other. Generally, it is too early to demand from the laptop computers, especially from thin and light, the same as from stationary monitors. We recommend before purchasing to "try on" yourself laptop computers' displays independently, corresponding to personal preferences (evaluating the maximum brightness, don't forget to cut off, cause there are many limiting factors in BIOS Setup and energy saving utilities, that are aimed to economize). Secondly, we don't attach a great meaning to the quality of build-in loudspeakers. What can we demand from the machine, which weights as one power unit of the middle multimedia acoustic system?

Usually, operating system MS Windows XP SP1 (according to model some critical updates) on NTFS partition, physically placed in faster region of the hard drive, is installed on the laptop computers. File system is chosen according to recommendation of the company Microsoft, and also according to those consideration, that laptop computers are trusted with very critical data, safety and security of which in FAT32 is lower. Besides , all laptop computers, that come to us from western companies, have pre-installed version of Professional on NTFS.

During the installation used packages Futuremark SYSmark 2001and Veritest PC Magazine Winstone 2004 offer for experimental clean deactivate temporary all automatic starting and resident programs, but we allow background work for standard utilities, bringing test closer to the real conditions; besides in the most of the systems you can't control energy saving and productivity without them.

Operating memory capacity in all models, passing our tests, isn't low 256 Mb. The most of the thin models has integrated video accelerators, that use for their own needs a part of the system memory (technology SMA), into northbridge of the chip set, so the available for the system capacity becomes lower. The influence of such decision is accessible.