Functional modes of hard disks and videoadapters depend on frequencies of buses to which the given arrangements together with the controllers are hooked up. For hard disks frequency modes are defined by bus PCI. For videoadapters depending on used type of the arrangement it can be or bus AGP, or PCI. It is necessary to notice, that for the motherboards released several years ago and oriented to usage of processors 486 and 386, it there can be buses VLB, MCA, ISA, EISA.

Frequencies of buses PCI, AGP, and it is frequent also their out-of-date predecessors, depend from installed frequency processor FSB buses (GTL +/AGTL +, Alpha EV6). Usually frequency buses PCI and AGP are installed by division frequency processor FSB buses. As an example it is possible to result widespread values frequency buses of processor FSB, AGP videoadapter and expansion cards PCI, often realised in motherboards.

Extended frequency motherboards with a chip set i440BX

* There is a probability of labile operation.

For the architecture of the majority of motherboards there are the resources giving possibility of adjustment of values of frequencies of buses AGP and PCI not only through change frequency FSB, but also appropriate coefficients of division frequency processor buses. It is carried out or by means of input of special parametres in BIOS Setup, or by means of special switches and crosspieces on motherboards. Change of values of frequencies of buses of the computer possible to select an optimum behaviour of maintenance of the arrangements controlled by means of given buses.

Usually as a part of a standard firmware there are no special resources for dispersal of hard disks. However speed of their operation depends from frequency buses PCI to which they are hooked up through appropriate controllers. In existence of such dependence it is possible to be convinced on an example of testing of the computer of a dispersal mode (overclocking) by program WinCheckIt (v2.03) at different values frequency processor FSB buses. This bus defines frequency of bus PCI, and through it and productivity of a hard disk. Estimations of productivity of the hard disk, received in the course of testing by program WinCheckIt (v2.03) at different values frequency buses PCI, are resulted in the appropriate table.

Productivity of a hard disk (WinCheckIt) at different values frequency PCI

Productivity of a hard disk (WinMark 99) at different values frequency PCI

It is necessary to mark, what not all hard disks treat kindly speeding up of the operation through increase frequency buses. For some types productivity increases, for others it even decreases. It depends both on type, and from a concrete copy of the given arrangements. Many modern hard disks, which size are exceeded by 10 Gbytes, on the raised frequencies with high-quality motherboards, for example, on frequency of 42 MHz and even above well work . Usually similar modes are impossible in case of usage of arrangements with size less than 1 Gbyte, processing techniques and which units are not so perfect as for more perspective models which have come to them in the stead. However, despite possibilities of modern hard disks of the high capacity, capable to work even at high values of clock rates of bus PCI, it is not recommended to maintain them at frequencies above 40 MHz. It is linked not only to rise of probability of glitch at realisation of write operations and data read-out and, as consequence, with loss of data, but also with deterioration of a temperature mode of maintenance of electronic and mechanical units of these arrangements. Here it is necessary to remind, that the hard disks, which construction provides great volume of the built in cache memory reaching of 2 Mb, and a high speed of rotation of disks, for example, 7200 turns in a minute, quite often demand cooling even in regular modes. Especially it is actual at usage of the several similar arrangements placed in a system unit of mesh sizes jointly by other high-powered accessories which operation are often characterised by high values of a heat release. In similar cases it is expedient to use adequate resources of cooling not only for the processor and the videoadapter, but for hard disks what, unfortunately, not always probably to realise. Thus, the limitations superimposed by nonoptimal temperature modes of maintenance and insufficient high-speed parametres of electronic and mechanical units of hard disks, are the main deterrents of dispersal of the given arrangements.

The modern high-powered videoadapters constructed on the basis of high-speed elements, admit the big changes of frequencies of the buses (AGP) in comparison with hard disks. But also they not always work stably on the high frequencies received as a result of dispersal of the processor. The table resulted above and the note well illustrate the given fact. As well as in case of hard disks, influence of the raised frequencies of bus AGP on productivity of a subsystem of video output can be observed on examples of dispersal of computers.

Some rise frequency buses AGP to which the videoadapter is hooked up, promotes growth of speed of processing of video data. Besides, the increase frequency this bus provides the pass-band extension (Bandwidth), that raises a transfer rate. All it, eventually, increases productivity of a video subsystem to proportionally growth frequency its buses. Thus features of the architecture and frequency properties of the electronic units making a basis of modern videoadapters, admit rather substantial growth frequency buses AGP. So, for example, the separate arrangements created with application of high-speed components, fulfilled on the newest processing techniques, save working capacity on the frequencies practically reaching 100 MHz, that almost 50 % more than the standard value of 66 MHz installed for bus AGP.

However possibilities of the given method of dispersal are limited. The resulted limits of growth frequency buses AGP concern, as a rule, separate successful copies of videoadapters. Usually limiting values a little bit more low. Thus growth frequency and productivity of the videoadapter is limited by separate units, whose high-speed possibilities do not allow them to work on higher frequencies. At the same time potential possibilities of other units remain non-realised.

Considerable, and the main thing — the depthbalanced increase in speed of operation of the videoadapter can be carried out by means of special software. The given resources allow to accelerate selectively, as a rule, operation of a video chip set and a video memory making a basis of the videoadapter. Thus possibilities of software on increase in productivity of a video subsystem can be added by increase frequency videoadapter buses — buses AGP.

The program allows to change videoadapter and screen monitor functional modes. Thus the change band frequency vertical scanning of the screen monitor (frequency frames) in the program is stretched to 200 Hz and limited to potential possibilities of the videoadapter and the screen monitor. Except regulation of this frequency, the given program gives the chance to change frequency video chip sets and a video memory, and also to hold testing of videoadapters.

Program PowerStrip supports video chip sets of corporations: 3Dfx, 3Dlabs, ATi, Cirrus Logic, Intel, nVidia, Matrox, S3, SiS, Trident, Tseng Labs etc . In long enough list such chip sets, as appear, for example: ATi Rage II Pro, CL GD543x/544x/546x, i740, Matrox G100, Permedia, PowerVR, Riva128/128ZX, S3 Vision86x, S3 Vision968, S3 Trio32/64, S3 TrioV +, S3 TrioV2/DX, S3 TrioV2/GX, S3 Trio3D, S3 ViRGE, S3 ViRGE/VX, S3 ViRGE/DX, S3 ViRGE/GX, S3 ViRGE/GX2, SiS 6326, Trident ProVidia 9685, ET6000, ET6100 and many other things.

The given program works with Windows systems 9x and Windows NT and allows to control operation of several honeycombs of models of screen monitors (practically all) among which screen monitors of such known corporations as are registered: Hitachi, MAG, Mitsubishi, NEC, Nokia, Panasonic, Philips, Sony, ViewSonic etc .

There are also other general-purpose programs calculated for a wide spectrum of videoadapters and screen monitors. However many manufacturers of videoadapters together with the products deliver the various programs incorporating, except functions of testing and optimal adjustment, a resource of optimisation of operation of a video chip set and video memory units. It is not seldom possible to familiarise with the given resources on appropriate sites in the Internet, and also for experts of the corporations which are engaged in sale and support of videoadapters.

Except the firm programs controlling operation of units of videoadapters, there are the numerous resources developed by enthusiasts of dispersal. To find and familiarise with them it is possible besides by means of the Internet.

In conclusion of this section it is possible to give an example dispersal and results of testing of Matrox Millenium G200 videoadapter. Thus, considering, that dispersal as the powerful tool of rise of productivity, concerns not only the systems constructed on the basis of the newest accessories, for testing has been selected the processor of Intel of Pentium 300A. Dispersal was carried out by standard resources of the motherboard.

• The test — 3D WinBench 98 (800 ґ 600 ґ 32)
• The motherboard — Asus P2B-S
• The working memory — 128 Mb CAS2 SDRAM
• The videoadapter — Matrox Millenium G200, AGP, 250 MHz RAMDAC, 8 Mb SGRAM, 128 Mb Graphics Aperture Size
• The processor — Intel Celeron 300A
• BIOS — Award Modular BIOS v4.51PG
• OS — Windows 98

Dispersal of accessories was fulfilled by increase frequency buses of processor FSB from standard value 66 to 103 MHz. Growth of productivity of a video subsystem is visually presented on fig. 1-3.

Results of tests