A complete illustrated Guide to the PC Hardware phần 10 pdf

An easy-read and illustrated Guide to SCSI, IEE1394 FireWire and USB. meters. Traditional SCSI only works within 3 meters. LVD has to compete with FireWire, which also has a powerful bandwidth. Adaptec have a SCSI-controller delivering up to 160 MB/sec. This unitcalled Adaptec SCSI Card 3950U2 uses two independent Ultra2 SCSI buses in one card. It connects up to 30 SCSI devices! What do you gain with SCSI? [top] Expensive but good. SCSI makes the PC a more expensive, but more versatile. The advantages are, that on the same PC you have free access to use many and good units: ● It is easy to add accessories as DAT streamers, CD-ROM recorders, MO drives, scanners, ZIP- and DVD-drives etc. ● You can use SCSI hard disks. ● You can use CDROM drives on SCSI, which may give a better performance. The advantages of SCSI hard disks SCSI hard disk are generally of higher quality than other disks.Typically, good SCSI disks come with a 5 year warranty. Traditionally they are faster than the EIDE disks. At 10,000 or 14,000 RPM they have shorter seek times. They also have a bigger cache. Another advantage is the large number of accessories, which can be attached. If you buy a 18 GB SCSI disk today, you will guaranteed need additional disk storage in a few years. Then you just add disk number two to the SCSI chain, and later number three. The system is more flexible than EIDE, where you can have a maximum of four units incl. CD-ROM. The SCSI hard disks can also adjust the sequence in the PC's disk read commands. This allows reading the tracks in an optimal sequence, enabling minimal movements of the read/write head. Quantum calls this technology ORCA ( Optimized Reordering Command Algorithm ). It should improve performance by 20%. Finally, the SCSI controller can multitask, so the CPU is not locked up during hard disk operations, which you can experience with IDE. SCSI hard disks can achieve substantially larger transfer capacity than the IDE drives, but they have the same bottle necks: the serial handling of bits in the read/write head, where the capacity is highly dependent on the rotation speed. SCSI is for servers However, today the importance of SCSI is decreasing except for use in dedicated servers. Modern CD-ROM and CD-RW drives work just as good on EIDE as on SCSI. USB has taken over when it comes to controlling units like scanners, cameras and Zip drives. Finally, modern EIDE-based harddisks have an extremely high quality compared to the products we had five years ago. Hence, there is no reason to prefer SCSI-based harddisk to the more inexpensive EIDE drives. http://www.karbosguide.com/hardware/module5c1b.htm (3 of 5)7/27/2004 4:09:40 AM An easy-read and illustrated Guide to SCSI, IEE1394 FireWire and USB. But for servers SCSI still has a market. Booting from SCSI disk If the hard disk has to be booted, traditionally it has to be assigned ID 0. If the SCSI controller has to control the hard disk, then the PC CMOS setup must be modified, so the (IDE) hard disk is not installed if not both types of hard disks are installed. The operating system will find the host adapter after start up and BIOS will be read from the hard disk through the adapter. New BIOSs allow a choice of booting from either IDE or SCSI disk. Fast and Ultra Wide The newest generation of SCSI hard disks are both fast, ultra and wide. Therefore, the best advice is to buy an adapter like Adaptec 2940UW2, which can handle the newest disks. IBM disks Allow me to advertise IBM's SCSI disks. They are fantastically good. Unfortunately, not many people know about them. I have had a few of them. They excel in high quality at reasonable prices. The physical construction is very appealing: The electronics are integrated in very few components. Everything exudes quality! And they are very quiet. You simply cannot hear them. 32 bit problems in Windows 3.11 Windows 32 Bit Disk Access has given problems with SCSI disks. For a long while, it was impossible to install a 32 bit driver in Windows 3.11 to the SCSI disk. This was solved in 1995 and there have been no problems with Windows and SCSI since then. Links About SCSI: SCSI Pro and DPT offer some information. ● Next page ● Previous page Learn more [top] Read about FireWire in module 5c3 Read about chip sets on the motherboard in module 2d Read Module 4d about super diskette and MO drives. Read module 5a about expansion cards, where we evaluate the I/O buses from the port side. http://www.karbosguide.com/hardware/module5c1b.htm (4 of 5)7/27/2004 4:09:40 AM An easy-read and illustrated Guide to SCSI, IEE1394 FireWire and USB. Read module 5b about AGP Read module 7a about monitors, and 7b on graphics card. Read module 7c about sound cards, and 7d on digital sound and music. [Main page] [Contact] [Karbo's Dictionary] [The Software Guides] Copyright (c) 1996-2001 by Michael B. Karbo. www.karbosguide.com. http://www.karbosguide.com/hardware/module5c1b.htm (5 of 5)7/27/2004 4:09:40 AM http://www.karbosguide.com/hardware/module5a1.htm http://www.karbosguide.com/hardware/module5a1.htm7/27/2004 4:09:40 AM Karbo's Software Tips Karbosguide.com A Few Software Tips The contents: Which are the advantages of Windows 98? About the swap files and RAM. About the disk cache. About temporary files (1). About temporary files (2). About file types - show only some of them! Use the desktop for favorite Internet addresses. Permanent folder for download in Internet Explorer. Choose a start page. Color changes in menus - a option in Windows 98. Replace opening screen in Windows. Upper case letters in folder names. Single click in Explorer - smart idea. TWEAK UI - the hidden tool in Windows 98. FAX program - what happened to that? Windows - autotexts in any program with ShortKeys. Windows - permanent, global and local macros Running out of space on my hard disk Enabling DMA on the harddisk Use MSConfig to alter the Windows start-up. ● Next page ● Previous page http://www.karbosguide.com/software/start.htm7/27/2004 4:09:41 AM Tips for Windows. Karbosguide.com. Software Tip 1 What are the advantages of Windows 98? ● Next page ● Previous page In my opinion and experience Windows 98 was an excellent operating system when introduced. At its introduction in the spring of 1998, some papers made the comment "it is not worth the money" and "there is not much new compared to Windows 95." I did not agree with them. Please support our sponsor. Here are some of the advantages compared to earlier versions of Windows: Generally better performance Generally Windows 98 utilizes the PC resources better: ● Memory management has been completely changed. It finally works. ● The file system is better integrated into the operating system, which gives new functionality. ● Program loading can be up to four times as fast. ● Hardware support is significantly improved with a new driver model, and all new chipsets etc. are supported. However these conditions may change. These improvements are sufficiently significant to justify an upgrade. Better user interface [top] Superficially the Windows 95 user interface has not changed much. But you need not dig down very deep to see many novelties. I am talking about small items with better adaptations in the Start menu, new tool bars, etc. But these small items are really very smart when you need to set the user interface. Better system tools The system tools are significant for the more demanding user, who really wants to know and http://www.karbosguide.com/software/01.htm (1 of 2)7/27/2004 4:09:42 AM Tips for Windows. be in command of the PC. A number of new tools have been added to Windows 98. They improve surveillance facilities. All of this will be thoroughly described in my upcoming "Windows 98 and hardware" booklet (or whatever the title will be). Stability Many will experience that previous instability is just gone. The PC can be left on for weeks on end without going down a single time. Many may laugh at this - "why should we pay to correct Windows 95 errors." That may be true, but consider the wasted time with PC's which fail and need to be restarted, etc. Cut the mustard and get 98 on your machines - then it works. Life is too short for lousy software! Windows 98 is not good enough In the years after the introduction of Windows 98, we saw new and faster hardware coming extremely frequent. We got faster CPU's, the clock frequency increasing 3 to 5 times in few years. Also harddisks became faster and RAM as well. Having a moderne PC with plenty of fast hardware, Windows 98 or Me (the later version) is not good enough. You need Windows 2000 or XP to benefit from the hardware. This is a fact. Just look at the way Windows 98 manages memory - it does not work using more than 128 MB of RAM. And that is a petty. If yOutlookwork with graphical applications like Photoshop or FireWorks, you will see a great performance using 512 MB RAM or more - but not with Windows 98/Me. ● Next page ● Previous page Copyright (c) 1996-2001 by Michael B. Karbo. http://www.karbosguide.com/software/01.htm (2 of 2)7/27/2004 4:09:42 AM Tips for Windows. Software Tip 2a About RAM and swap file ● Next page ● Previous page In Windows 95 and 98 it is important to understand the of the relationship between: ● Amount of RAM in the PC ● Size of and control of Disk cache ● Free memory ● Size of the swap file Windows are in all versions (as all Microsoft software) a very resource demanding operating system. Then you might ask, why bother to use Windows? We all know the answer: The Microsoft Office packages are undoubtedly the finest, most user friendly and most thoroughly planned office programs on the market - no question about that. They can work satisfactorily on your PC, but it requires some hardware. A lot of hardware indeed. The processor should be fast, as all modern processors are. Plenty of RAM and a roomy and fast hard drive is also very desirable for running Windows. The need for RAM Windows gobbles up memory. Therefore, sufficient memory is essential for its satisfactory performance. Try to check how much you really need - you will be surprised. The memory comes from two locations: ● The installed RAM ● The swap file, which is created automatically, when you run out of RAM. Windows is clever using the swap file . It "extends" its RAM to the hard disk. If you only have 64 MB RAM in your PC, you can be assured that you have a sizable swap file on your disk. Controlling the swap file You may choose which drive, you place the swap file. Some experts prefer to place the swapfile on a separate partition, which only is used for the swap file. That way, the swapfile does not interfere with the other disk data, which become more easy to defragment. http://www.karbosguide.com/software/02a.htm (1 of 3)7/27/2004 4:09:42 AM Tips for Windows. You deside the placement and size of the swapfile using the System Properties dialogue box. Here you see it from Windows 2000: We recommend that you limit the swapfile to a size of 512 MB using Windows 98/Me. If you use Windows 2000 (which is working a lot better than 98/Me) you should leave Windows to deside the size of the swap file. Anyway, you need to keep an eye on the swap file. In Windows 95 many breakdowns originated in swap file use. But luckily Windows have improved a lot; Windows 98 is is better at controlling RAM and swap file than Windows 95 is. http://www.karbosguide.com/software/02a.htm (2 of 3)7/27/2004 4:09:42 AM Tips for Windows. Windows 98 has a better algorithm to control RAM etc. The swap file is still there, and it is big - but that does not have to be a problem. Windows only reads to and from the swap file, while no work is done on the PC. In that way we do not even notice that there is a swap file. In the Windows versions 2000 and XP there is no need to worry about memory management, it works fine (but please use 512 MB RAM). No swap file? Some experts recommend if possible to eliminate the swap file in Windows 98. It sounds great but is not not very smart in practice. The problem arises from the extremely lousy memory management you find in Windows 98. Any onboard RAM above 256 MB find no use! Even upgrading from 128 to 256 MB gives almost no benefit; Windows still runs out of memory all the time. ● Next page ● Previous page Copyright (c) 1996-2001 by Michael B. Karbo. http://www.karbosguide.com/software/02a.htm (3 of 3)7/27/2004 4:09:42 AM [...]... of the problems appeared to be that the Serial Presence Detect (SPD) chip included on SDRAM DIMMS was missing in some modules This SPD was crucial to the MCH A solution was to add a 150 ohm resistor between the Memory Translator Hub and the SDRAM Wisely Intel finally gave up all this business In the end they had to recall a million of Intel motherboards and had to give away RDRAM in large numbers to. .. http://www.karbosguide.com /hardware/ module2d09.htm (2 of 5)7/27/2004 4:09:52 AM An illustrated Guide to the i820 chip set This design but a heavy strain on the PCI bus, having a 133 MB/sec bandwidth All data to between RAM and disks, network adapters and other I/O boards such as PCI-based graphics controllers had to pass through the PCI bus In the new design, we first saw within the i 810 chip set, we have... companies to implement AGP 4X in the chip set Using AGP 4x, the bandwidth to the graphics subsystem has doubled from 533 MB/sec in AGP 2X to more than 1 GB/sec: http://www.karbosguide.com /hardware/ module2d10.htm (2 of 4)7/27/2004 4:09:54 AM An illustrated Guide to the i820 chip set This is good for all gamers 3D gaming needs a powerfull channel to RAM to produce high quality screen frames The RDRAM channel... Intel to produce http://www.karbosguide.com /hardware/ module2d08.htm (3 of 4)7/27/2004 4:09:50 AM An illustrated Guide to the i820 chip set boards using PC1 33 RAM as well as RDRAM A sound idea, indeed DDR was never planned, since Intel is not allowed using this type of RAM, according to their agreement with Rambus (covering the years 2000-2002) q q Next page Previous page [top] Learn more Read about the. .. AM An illustrated Guide to the i820 chip set The Memory Controller Hub (MCH) Please support our sponsor Central in the chip set is the Memory Controller Hub This device controls the data flow to and from RAM The idea is to assign maybe two or four RAM channels for higher bandwidth Here is my early guess on the design: The idea of using a Memory Translator Hub as you see above, was that it would enable... features from i 810 plus a lot of great news q q Next page Previous page [top] Learn more Read about the Pentium in module 3c Read about the Pentium II's etc in module 3e [Main page] [Contact] [Karbo's Dictionary] Copyright (c) 1996-2001 by Michael B Karbo KarbosGuide.com http://www.karbosguide.com /hardware/ module2d06.htm (7 of 7)7/27/2004 4:09:46 AM [The Software Guides] An illustrated Guide to the. .. contents: q q Caminogate: No PC1 33 RAM, no MTH The hub-based architecture http://www.karbosguide.com /hardware/ module2d09.htm (1 of 5)7/27/2004 4:09:52 AM q q Next page Previous page An illustrated Guide to the i820 chip set Caminogate: No PC1 33 RAM, no MTH Today we know the i820 chip set is used only with RDRAM; Intel failed to produce a reliable MTH (or Memory Conversion Hub (MCH), as it later was named) One... instead of "bridges": http://www.karbosguide.com /hardware/ module2d09.htm (3 of 5)7/27/2004 4:09:52 AM An illustrated Guide to the i820 chip set q q Next page Previous page Learn more Read about the Pentium in module 3c Read about the Pentium II's etc in module 3e http://www.karbosguide.com /hardware/ module2d09.htm (4 of 5)7/27/2004 4:09:52 AM [top] An illustrated Guide to the i820 chip set [Main page]... Integrated Audio-Codec 97 controller enables software audio and modem by using the processor to run sound and modem software It will require software, but using this you need no modem or soundcard This feature is smart if you do not use audio or modem on a regular basis It adds a heavy work to the CPU, which has to act as a modem and as a sound card beside its regular tasks Karbo's conclusion [top] The. .. the first year of i820 Therefore, i820 never became popular q q Next page Previous page [top] Learn more Read about the Pentium in module 3c Read about the Pentium II's etc in module 3e [Main page] [Contact] [Karbo's Dictionary] Copyright (c) 1996-2001 by Michael B Karbo KarbosGuide.com http://www.karbosguide.com /hardware/ module2d10.htm (4 of 4)7/27/2004 4:09:54 AM [The Software Guides] An illustrated . not use audio or modem on a regular basis. It adds a heavy work to the CPU, which has to act as a modem and as a sound card beside its regular tasks. Karbo's conclusion [top] The 82 810 controller. AM http://www.karbosguide.com /hardware/ module 5a1 .htm http://www.karbosguide.com /hardware/ module 5a1 .htm7/27/2004 4:09:40 AM Karbo's Software Tips Karbosguide.com A Few Software Tips The contents: Which are the advantages of Windows 98? About the swap files and RAM faster than the EIDE disks. At 10, 000 or 14,000 RPM they have shorter seek times. They also have a bigger cache. Another advantage is the large number of accessories, which can be attached. If