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What do you do with old 286 and 386 computers? Most people “chuck ’em” but for just $15 you can buy a new 486 mother­ board, do a transplant and turn it into a useful machine. Here’s how to go about it. Doing a By GREG SWAIN Lazarus on an old computer S CROUNGING OLD PCs has never been easier. They’re thrown away during council cleanups, given to employees during company upgrades and available for a pittance at garage sales. Just think of the number of machines that were scrapped as insurance against the dreaded Y2K bug – it’s just a matter of being in the right place at the right time. One of our staff members was in the right place recently, when his local pharmacist threw out an old 386 machine complete with supporting software (DOS 6.22 and Windows 3.11). He wanted a second machine for use at home but didn’t want to spend much money, so 4  Silicon Chip he brought it in to see if the machine was worth upgrading. At first glance, the hardware all looked in pretty good nick, although it was a bit grotty. It had obviously been used next to a printer because both the keyboard and the monitor were stained black from toner. By contrast, it was reasonably clean inside the system case but we did notice lots of corrosion around the battery. That meant that the old 25MHz 386 motherboard was almost certainly defunct but it was no loss – a 386 motherboard is next to use­less. It was time to take stock and a quick inventory – the price is right and there are lots of applications for a refurbished ma­chine. For example, it could be used as a word processor, a printer server, a dedicated fax machine, or even as an Internet firewall. It could also be used for networking experiments or for testing applications that you’re not too sure about and don’t want to risk on your main machine. The $15 motherboards come fitted with a “UMC” brand 40MHz 486SX processor as standard but you can set the bus speed to 25MHz, 33MHz or 40MHz if you wish to use a different processor. In fact, the unit can cater for Intel, AMD and Cyrix processors up to DX2-80 and DX4-75/100 in the standard Socket-5 configura­tion. If you have an Intel DX2-66 processor, for example, you can easily swap the processor to extract a bit more performance. A DX4-100 would be even better! You set the bus speed and various other parameters to suit the processor by changing links on the motherboard, as set out 1 Apart from the motherboard, it all looked pretty good inside! This in the manual. Also on the board are six old PC was an ideal candidate for a motherboard transplant. expan­sion sockets (five 16-bit and one 8-bit), plus four 30-pin and one 72-pin revealed the following goodies: (1) a sturdy desktop SIMM (single in-line memory) sockets supporting up to case with working power supply; (2) a 120MB hard 32Mb of RAM. disk drive; (3) a 1.44MB floppy disk drive; (4) a 1.2MB There is also provision on the board for up to 512KB floppy disk drive (OK, you can chuck that); (5) a generic of cache RAM but no TAG or cache RAM is fitted. You video card; (6) a rather nice D-Link network card; and can’t expect that for $15 but if you’re lucky, you can use (7) an I/O (input/output) card with serial and parallel the TAG and cache RAM from your old motherboard. ports plus connectors for the disk drives. Of course, it will still run without cache RAM – it just As for the monitor and keyboard, they may have won’t be as fast. looked grotty but they worked perfectly when tested One drawback is that there is no provision for I/O with another comput­er. They were both good-quality on the motherboard; ie, no serial or parallel port conNEC units and were worth cleaning up. nectors and no connectors for disk drives. Again, this There was just one thing missing – a mouse but we isn’t a problem if you have an I/O expansion card. Most had one spare anyway. 286, 386 and early 486 computers came with separate And that’s all quite typical of most old computers I/O cards but if yours didn’t, you’ll have to scrounge that have been rescued from the tip. Most of the hardone from another old computer or pick one up at a flea ware, including the disk drives, is usually quite OK but market. there will often be problems with the motherboard. If In case you’re wondering, the motherboard comes it’s a 286 or 386, the mother­board isn’t worth keeping even if it still works OK. Usually, however, they will have been damaged by a leaking battery and the same goes for many 486 motherboards as well. Apart from that, most old computers generally need a good clean up. The keyboard is always dirty and sometimes the keys stick because it is full of dust and fluff. There is also often quite a lot of dust inside the system case and it seems that no-one ever cleans monitors. New motherboard So what was needed to turn our old 386 into a useful work­ing computer? Simple – a good clean up and a motherboard trans­plant. The first part is easy and for the latter, we had just the unit in mind. If you want a low-cost motherboard, Oatley Elec­tronics has a really good deal – a brand new 486 motherboard for just $15 or three for $30. But why would you want to do it? Well, why not? 2 $15 buys you this brand new 40MHz 486SX mother­ board (without the memory) from Oatley Electronics. It’s just the shot for trans­planting into an old 286 or 386. A Pentium motherboard would be even better! March 2000  5 3 Step 1 was to attack the keyboard. Undoing four screws along the top rear gives access to the innards. 4 The key carrier plate was lifted clear after prising open several retaining clips using a flat-bladed screwdriver. fitted with a recent Award BIOS and supports LBA mode (logical block address­ing) for hard disk drives. Put simply, this means that the BIOS can support modern large-capacity disk drives and is not just re­stricted to drives of up to 528MB. So if you’ve got a 1.6GB drive, for example, you won’t need a special device driver to access its full capacity. If you’re using a motherboard with a BIOS that doesn’t support LBA, you will need to obtain a special driver to translate the drive geometry. Perhaps the best known of these are Ontrack Computer System’s “Disk Manager DiskGo” (as used by Seagate) and Western Digital Corporation’s “Data Lifeguard”. If you want something better than a 486, see if you can “acquire” a discarded Pentium motherboard and processor. This will allow you to run Windows 95/98 at a fair clip provided you fit enough memory (ie, at least 16MB). OK, it was time to get to work and resurrect our old 386 machine. The first thing to do was to disassemble and clean that grotty keyboard. Undoing four self-tapping screws along the rear top edge allowed us to lift the front cover clear. This done, we removed the black plastic carrier plate, complete with all the keys, by gently prising open a number of retaining clips using a flat-bladed screwdriver. There were three small green indicator LEDs clipped into the top, righthand corner and these were removed and placed to one side. As expected, the keyboard was full of dust and this one also gave up numerous paper clips and metal staples. A soft brush got rid of the dust, while the key/carrier plate assembly was sprayed with “Nifty” (a household cleaner) and scrubbed clean in a tub of water using an old toothbrush. It came up looking like new, as did the top cover when we gave it the same treatment. The plastic base was cleaned by wiping it with a cloth sprayed with “Nifty”, taking care not to touch the plastic key­board membranes or the circuit boards. Naturally, the key/carrier plate assembly must be thorough­ly dried before the keyboard is reassembled. It’s not just suffi­cient to dry the outside of the assembly because a lot of water becomes trapped in the key guides. This water can be dislodged by repeatedly tapping the assembly on your hand, after which you can use a hairdryer on a low setting to complete the process. In our case, we also left the key assembly to dry overnight before carefully putting the keyboard back 7 It’s a good idea to write down the lead colour coding for the front panel LEDs and switches. This makes it easier to place the connectors on the new motherboard later on. 8 Out with the old – the two power supply plug connect­ ors were the last be released before the old motherboard was lifted clear of the chassis. Keyboard capers 6  Silicon Chip 5 Time to clean up – spraying the keys with “Nifty” and scrubbing them with an old toothbrush worked like magic. 6 A soft brush was used to remove the dust, paper clips and staples before the keyboard was reassembled. together. When we had finished, it looked as though it had just come out of the fac­tory. By the way, there are lots of variations when it comes to keyboard assemblies. It’s really just a matter of using your common sense. The monitor also responded well to the “Nifty” treatment but again you have to be careful. Don’t allow fluid to find its way through the ventilation slots and onto the circuit boards. If you do, the monitor could very well expire the next time it’s turned on. Now for the motherboard transplant. If you have a working system, it’s a good idea to first fire it up and take a peek at the hard disk parameters in the system BIOS. Make a note of these because you will need to re-enter them later on. If the system is defunct, just ignore this step. Most hard disk drives have their parameters printed on the drive label although you may have to remove the drive to see them. If it doesn’t, it’s quite easy to obtain the parameters by visiting the manufacturer’s web site. Alternatively, the Award BIOS supplied with the Oatley motherboard has an IDE hard disk drive auto-detection utility which should make the job easy. Our next step was to remove the power cord, open up the system case and remove the expansion cards. We didn’t completely remove the I/O card, however. Instead, we left all the cables connected to it and sat it on top of the power supply. Next, we removed the two power connectors to the mother­board and the connectors for the front-panel leads. These leads ran to the front-panel indicator LEDs, to the Turbo and Reset switches and to the keyboard lock. It’s a good idea to write down the colour coding for these as you go, to save tracing them back to the front panel later on. Removing the motherboard now involved undoing two retaining screws at the rear and sliding it sideways until the plastic standoffs cleared the metal keyways in the chassis. It then lifted clear, after which we transferred the plastic standoffs to the appropriate locations on the new board. If you are undertaking the same exercise, you may find that there is a slight variation on this theme but it will be obvious what you have to do. Test fitting the new board into the case will quickly indicate which holes should be fitted with plastic standoffs and which should be reserved for the retaining screws (these go into tapped metal standoffs). 9 More cleaning – a soft brush and a vacuum cleaner were used to spring-clean the chassis. This makes it more pleas­ ant to work on and is good for long-term reliability. 10 The plastic standoffs must be removed from the old board and fitted to the new motherboard. In some cases, it may be easier to fit the standoffs to the chassis first. Removing the hardware March 2000  7 11 RAM for free – our four 1MB SIMMs came from an old 286 motherboard. It sure pays to keep this stuff because you never know when it’s going to come in handy. Looking For Drivers? Go Directly To The Web O NE THING THAT’S usually missing when you acquire an old computer are the original setup disks, containing the driver files, for various hardware items. This particularly applies to video cards, soundcards, network cards, CD-ROM drives, printers and modems. By itself, Windows 95/98 usually makes a pretty good fist of identifying your hardware and supplying the correct driver from the Windows CD-ROM. But that doesn’t always happen, in which case the answer is to download the appropriate driver from the manu­facturer’s website. If you’re looking for driver files, here are a few websites for you to try: (1) www.windrivers.com (all sorts of links to drivers plus help for identifying unknown hardware such as motherboards, modems, video cards, sound cards and network cards). (2) www.winfiles.com (lots of links to manufacturers, driver updates, bug fixes and other goodies here). (3) www.geocities.com/SiliconValley/6708/index. html (lots more links for you to try). Having trouble identifying the manufacturer or model of some hardware? If it’s got an FCC (US Federal Communications Commission) ID number, you can search for it at www.fcc.gov/oet/fccid/ Finally, there’s also help for identifying unknown modems at www.56k.com/trouble/noname.shtml 12 In with the new – the new motherboard, complete with RAM, is installed by sliding the plastic standoffs into the keyways in the case. Don’t forget the retaining screws. Before throwing the old motherboard in the rubbish bin, take a good look at the type of memory (RAM) that’s fitted to it. If it uses 256KB, 1MB or 4MB 30-pin SIMMS or 1, 2, 4, 8 or 16MB 72-pin SIMMs, you’re in luck and the memory can be salvaged for the new board. We weren’t so lucky – our old 386 motherboard used DIL (dual in-line) memory which is worth­less. Once the old motherboard is out, it’s a good idea to remove any dust from inside the case using a soft brush and a vacuum cleaner. While you’re at it, you should also brush away any dust that’s on the expansion cards. Usually, it will be more convenient to fit the memory to the new motherboard before installing it in the case. We had four 1MB 30-pin SIMMs, previously salvaged from another old machine, sitting in a drawer, so we fitted that (yes, it really pays to keep this stuff). OK, so 4MB of RAM isn’t much but it’s usually adequate (barely) for a machine running Windows 3.1x. If you don’t have any memory that’s suitable, try to scrounge some from another old machine. The aim is to spend as little money as possible because old computers are not worth spending big bucks on. If you do have to buy memory, you’ll find that the 72pin stuff is considerably cheaper than the older 30-pin stuff. Also, if you’re using the Oatley board, be sure to Want to identify a hardware item? Try www.windrivers.com or if it has an FCC ID number, search for it at the FCC website listed above. 15 We’re fastidious, so we removed the old 1.2MB floppy drive and brushed away the dust. OK, so 1.2MB drives are now useless but we didn’t have a blank to take its place. 8  Silicon Chip 13 All hooked up and ready for the expansion cards. Note the arrangement for the power supply connectors – their black leads go to the centre pins of the power socket. 14 We connected the disk activity indicator LED to a pair of terminals on the disk drive itself. Usually, however, you will find suitable terminals on the motherboard. check the memory configuration table in the manual. Note that the largest 72-pin SIMM that you can use by itself is 8MB. A 16MB 72-pin SIMM can be fitted but this must be matched with 4 x 4MB 30-pin SIMMs in the other memory slots (giving a total of 32MB). How much RAM should you use? That depends on the operating system and applications you intend running. If you intend running Windows 95/98, for example, then you should aim for a minimum of 16MB. On the other hand, 4-8MB should be enough for Windows 3.1x. be oriented with its positive lead to pin 1. If you don’t know what a particular connector is for, the easiest way to find out is to trace it back to the front panel. Note that the Oatley board doesn’t have terminals for the hard disk activity LED. We solved that minor problem by plugging the connector directly into the relevant terminals on the hard disk drive itself. At this stage, it’s a good idea to take a look at the power switch. Make sure that the spade connectors are pushed all the way home on the switch terminals and that they are all well-insulated. The Earth lead at the switch end should be securely fastened to the case metalwork and a multimeter should indicate a good connection between the metalwork and the earth pin of each IEC mains socket at the rear of the computer (ie, you should get a reading of zero ohms). Fitting the new board Once all the memory had been loaded, we slid the mother­board into the case, installed the retaining screws and plugged in the two power connectors. How do you know which way around the two power connectors go? Easy – black goes to black which means that the black leads on the connectors go to the middle of the socket. Depending on the case and the location of the power supply, it may sometimes be easier to install the power connectors before sliding the motherboard into position. This particularly applies if the power socket sits directly beneath the power supply when it is in position. It may also sometimes be easier to install the plastic standoffs in the case before fitting the motherboard. That way, the motherboard can simply be positioned over them and clipped into position. It’s up to you to choose the easiest method. Finally, we refitted the various expansion cards (ie, the video, network and I/O cards) and installed the front panel wiring connectors. These connectors are for the Turbo and Reset switches, the Turbo LED, the Speaker Connector and the Keylock & Power LED Connector. The locations of these are clearly shown in the manual and are also shown on the board itself (this also applies to most other motherboards). How do you know which way around the connectors go? The Turbo and Reset switches can go either way, while the Keylock & Power LED connector must be oriented so that the positive lead from the power LED goes to pin 1. Similarly, the Turbo LED con­nector must Booting up Before applying power, it’s a good idea to carefully check your work. In particular, we checked that the 16 Make sure that the expansion cards are properly seated before tightening the backplane connector screws. Also be sure to plug the 16-bit cards into the 16-bit slots. March 2000  9 Adding Another Hard Disk Drive And All That Guff O NE OF THE DRAWBACKS of old computers is that the hard disk drive is usually of quite limited capacity. Many 286 machines, for example, came with a 40MB drive, while 386s and early 486s usually have a hard disk drive ranging from just 80MB to 240MB. By contrast, DX2-66 486 machines often have a 500MB or better hard disk drive which will be adequate for many applications. If the disk drive isn’t up to the job, the answer is to swap it for something bigger or perhaps add a second drive. Once again, the trick is to scrounge something from a defunct machine. This shouldn’t be too difficult, particularly if you are building one good machine from several write-offs. Most hard disk drives that you will encounter are IDE (integrated disk electronics) types and these connect to the IDE port on the motherboard or I/O card via a 40-way cable. This cable is usually fitted with two connectors at one end so that you can connect two disk drives, one configured as a “master” and the other as a “slave”. The master or slave configuration is set using jumper links on the back of the drive. For example, if only one drive is connected to an I/O cable, it’s generally configured as a “mas­ter”. Note, however, that some drives must be set to a “single” configuration if used on their own. On other drives, the “master” and “single” jumper settings are the same. If two drives are connected to the same cable, one is con­figured as a “master” and the other as a “slave”. Note, however, that if the second drive is used on its own on another I/O cable (some motherboards have two IDE ports), then it must be set to the “single” drive (or master) configuration. Just to confuse matters, most hard disk drives also come with a pair of jumper pins labelled “CS”, or “Cable Select”. This configuration is used only with a special I/O (CS) cable which has the disk connectors clearly marked; eg, drive 1 and drive 2 or master and slave. If you use a CS cable, you just set both drives to “CS” before connecting them to the cable. You’re not restricted to just using hard disk drives on All hard disk drives come with three or more pairs of jumper pins, usually located between the I/O socket and the power socket. These let you configure the drive as a “master” or as a “slave”, where more than two drives are used on the same cable. 10  Silicon Chip the IDE ports, by the way. For example, you can add an IDE CD-ROM or a ZIP drive if you wish but be sure to configure the drive as a “master” or “slave”, as appropriate. Having installed the new disk drive, don’t forget to enter its parameters (or run Auto Detect) in the BIOS setup so that the system will recognise it. After that, it will have to be parti­tioned and formatted (if this hasn’t already been done) before installing the operating system. A word of warning here – if you’re moving a disk drive across from an existing system and want to keep your data, be careful with Auto Detect. If you do use it, you may find that the machine won’t boot up or, if it’s a nonboot disk, you may no longer be able to access files or the files may appear to be corrupted. The reason for this is that Auto Detect doesn’t read any settings that may have been manually assigned to the drive in the previous installation. Instead, it retrieves the drive’s parame­ters from a ROM (read only memory) that’s incorporated into the drive itself. This means that Auto Detect will cause errors if any previously-assigned parameters differ from those stored in the ROM. Naturally, this doesn’t matter if you no longer need the data stored on the drive. If that is the case, you can just reformat the drive and carry on with the new settings. On the other hand, if you wish to keep the existing data, you will have to manually assign the required drive parameters if Auto-Detect causes problems. By the way, don’t try to fix any disk errors using a disk management utility such as ScanDisk if Auto-Detect is causing problems. If you do, you will almost certainly corrupt your data. Another factor to consider is that old 386/486 motherboards generally have BIOS limitations when it comes to recognising hard disk drives bigger than 528MB. Other more recent BIOSes can’t “see” past 4.3GB or 8.6GB. One way around this is to use BIOS translating software. In each case, you should visit the manufac­turer’s website and download the software that’s right for your hard disk drive. It’s important to obtain and install the latest version of any BIOS translating software. That’s because older versions aren’t compatible with FAT32. With an older version, if you installed Windows 98 and later converted to FAT32, you would no longer be able to access the drive. Yes, there is a way of re­trieving the situation but you don’t want to know about it. Another way around the problem, provided your motherboard has a spare PCI slot, is to purchase an IDE controller card with its own on-board BIOS. But hey, you’re starting to spend money on an obsolete machine and that’s not the idea here. Finally, remember that the operating system itself may have limitations when it comes to recognising large hard disk drives. In particular, the FAT16 partitions created by DOS, Windows 3.1x and Windows 95A are limited to 2.1GB so if you have a 4.3GB drive, for example, the trick is to split is into two 2.1GB partitions. Windows 95B, Windows 98 and the recently released Windows 2000 can all use FAT32 partitions and have no trouble recognising large disk drives. 17 Into the home straight – the top cover on this old PC slides on from the front . . . 20 The resurrected machine, all cleaned up and running Windows 3.11. Now where did we put that old CD-ROM drive that’s been lying around? 18 . . . and is secured using screws at the rear and along the sides. 19 The best bit! – one of our staff members nicked the EEPROMs from the old motherboard before we threw it in the bin. Best place for an old 386SX motherboard, really. power connectors were correct. Installing one of these the wrong way around is a sure-fire way of cooking the motherboard! Check also that the disk drive cables haven’t come loose and don’t forget to connect the monitor, keyboard and mouse before switching on. In our case, we had a fully working system as soon as we had configured the system BIOS. As usual, the BIOS Configuration Setup is entered by pressing the Delete key at the on-screen prompt while the system is booting up. You then select the Standard CMOS Setup option and enter the details for the hard disk drive (HDD). This can either be done manually or you can go back to the main menu and run the “IDE HDD Auto Detection” utility that’s included in the Award BIOS. You also have to set the time and date, select the types of floppy disk drives fitted and select the type of video card used (invariably EGA/VGA). The other setup utilities let you set some of the more advanced features but unless you’ve changed the processor, you can stick to the defaults. Of course, you can swap the floppy disk drives, select a different boot drive sequence or turn NumLock off if you want to. If you’ve swapped the processor then you will need to alter the BIOS setup to suit. This is clearly illustrated in the manual that comes with the Oatley motherboard. Once we’d saved the BIOS setup, the machine booted up into glorious DOS followed by Windows 3.11. But who wants to use Windows 3.11? Now if we can just add more RAM, upgrade to Windows 98, install a bigger hard disk drive, add a CD-ROM drive and . . . SC March 2000  11