Saturday, August 25, 2007

One Keyboard, Two Computers

This past summer, I experienced an extended time period when I was struggling to make my desktop computer work properly. Some of that time went to hobbying, where I was experimenting with different possibilities; but I don't think I would have done that hobbying if I had been at liberty to proceed with my primary tasks. It think it was more a matter of making the best of a bad situation. The experience certainly enforced a sense of dependence upon the desktop computer. While I was not entirely happy with that, at this point it was a matter of facing up to that reality. At some later time, I felt, it might be possible to be more laptop-oriented, or to use computers in libraries or otherwise to be less dependent upon the home desktop computer; but that was not the current reality. The question, therefore, was how to make the best of the home computer dependence -- how, in particular, to be as efficient as possible at it. Of course, the more efficient I became at the home computer, the less likely I would be to find that I could achieve comparable efficiency elsewhere. That, too, needed to be a question for another day. I felt that such a day would come -- that my own needs would change over time, and that technologies would continue to develop. In a few years, I hoped, I would be able to do much of what I needed to do at any number of locations. I found two aspects of the home setup to be particularly useful. One was the scanner; the other was the dual monitor setup. There was no question but that having two monitors made me far more efficient. For example, I could read a PDF document on one screen and write about it on the other. The scanner was not as constantly useful, but I had developed a system in which most paper materials quickly got scanned into PDF format, which facilitated very fast document retrieval. The scanner was thus something that I needed badly, but not at every moment. After the summer experience, I decided that, for the time being, I could no longer pretend that my laptop could serve as a second computer at times when the desktop computer was tied up or malfunctioning. Those times, I began to realize, were more frequent than I had recognized. I think I had gotten used to sitting through various delays, and was no longer naturally inclined to be impatient. So if Windows XP froze up, or began functioning slowly, I would wait for it, or would go tinker with something, and basically just wait for it to come around. Sometimes, of course, my strategy for dealing with a slowdown or an apparent system malfunction would be to reboot, to use System Restore, to run some drive or system diagnostics, to restore a previous drive image, or otherwise to remove the system from active service for a period of minutes or, occasionally, for hours. My summer's experience involved extensive exposure to those periods of system maintenance or malfunction. I found that the laptop was not a sufficient stand-in, at those times, for several reasons. It did not have multiple monitor support. It was slow. It did not have the contents of my desktop computer's hard drives. Its keyboard was not as good, and if I used it extensively, my hands would get sore. And so forth. I recognized these various facts because the summer experience had been very frustrating, but also because a new alternative began to present itself. Some years earlier, it had been common for me to have two computers. If I had had two computers during this past summer, I could have saved a great deal of time by swapping parts between the two for testing purposes. If the part worked in one computer but not in the other, I could have some suspicion that this particular part was not the reason for a system malfunction. The summer experience taught me to take my desktop computer setup more seriously, as I say, and in particular it told me that I should have had a second computer available for diagnostic and hobbying purposes. I did not plan to undertake much hobbying once the primary computer was together. But now I realized that I should nonetheless have a secondary desktop computer on hand because, too often, these times of malfunction arrive when it is least convenient. Doing so seemed particularly wise if, as I was beginning to recognize, there might actually be a considerable amount of lost time, each week, as I sat waiting for the computer. So I began to choose components for a second computer. It quickly became apparent that having a second computer would only partly address the dual monitor issue. I could manually unplug both monitors from the primary desktop computer, and plug them into the secondary desktop computer; but I would probably do that only for longer periods of primary computer downtime. This meant that, if I was going to rely upon manual means of switching over to the secondary computer, I would probably use that computer only a few times a week. And that, in turn, meant that it would not be useful for the large majority of my tasks. My research revealed that there is a device called a KVM switch (short for keyboard-video-mouse), and that some of these KVM switches also included ports for speakers as well as USB ports. That is, you could connect a number of devices -- including your printer, scanner, keyboard, monitors, and speakers -- to the KVM switch, and you could use that switch to change instantly from one computer to the other. So as soon as the primary computer began to slow down, or when it would need a reboot or maintenance, I could set it on that path, and could then turn my attention to the secondary computer. This way, the secondary computer would be generally available for a variety of projects. The possibilities expanded even more when I realized that I could also connect an external USB drive to this device, and could then access that drive from either computer. In that scenario, there might be some projects that would reside exclusively on the primary machine, and other projects that might reside exclusively on the second machine, but there could also be projects that were equally available to both. Of course, I wished I had thought of this possibility earlier, during the summer, when I was buying and configuring my primary desktop computer. My reason for upgrading to that computer was that there were times when my existing computer was not able to walk and chew gum at the same time. A plan of dividing the workload between two computers might have enabled me to keep that computer and merely add a second one to my collection, without disrupting my workflow as I made the transition from one to the other. It also occurred to me that having a shared drive could make it far easier to transfer large files and folders back and forth between the two computers -- and possibly also with the laptop, if it should develop that I could temporarily plug it into the KVM switch in place of the primary or secondary computer. A shared drive might also be useful if it proved possible to use the secondary desktop computer as a test bed for an Ubuntu installation. (I had taken some steps toward Ubuntu previously, and was now waiting for the next version of Ubuntu to arrive before proceeding further.) I wasn't sure whether the KVM switch would work if one computer was running WinXP while the other was running Linux, though it seemed to me that the two computers should not be seeing each other through this switch, and therefore that it shouldn't matter what operating systems they were running. That, anyway, was something I could learn about as I went along; it was not crucial at this point. It seemed I could afford to spend some money on the KVM switch, in the sense that it would spare me from having to buy one or two more monitors for the secondary desktop computer. Of course, I did not want the clutter of additional monitors anyway. My workspace also did not have a space for a second keyboard; I would have had to use one at tabletop height, rather than at the lower keyboard tray height that had proved to be kinder to my hands and wrists over the years. I had also found that my workspace tended to be organized around the primary keyboard, and that I naturally gravitated back to it. That is, if I wanted to be switching immediately to the secondary computer as soon as the primary one ceased to be available, it seemed I was best advised to make that secondary computer readily available within my normal seating arrangement. My research included the Wikipedia page for KVM. That page informed me that I wanted an electronic rather than manual switch, for switching between computers, because the electronic kind was able to persuade the computer that the monitor, keyboard, and mouse were still connected. So if the system rebooted as part of a maintenance procedure, for example, it would keep right on booting; it would not freeze at the part of the bootup procedure that checks for a working keyboard. Wikipedia also told me that there were software alternatives that would allow two computers to be connected to the same devices, but these did not sound appealing because (a) I did not want software dependency, (b) I wanted operating system independence (see remarks about Ubuntu, above), and (c) these, too, could be useless in reboot and other maintenance situations. As I reviewed other webpages, some interesting points came to light. One was that some KVM switch manufacturers apparently devised their cables to be multipurpose. Instead of having double sets of each keyboard, mouse, and video cable, it looked like their cables combined all functions into one. That way, you would have only a couple of cables leading from the device (which might be sitting on your desk), and the separate cords (for video etc.) would diverged only near the other end of the cable, so that you could plug the various devices into the video, audio, and keyboard jacks on the back of your PC. Another way to minimize the worry about cables was to buy a KVM switch that would allow hotkey switching from your keyboard. If you didn't need to push an actual physical button on the device in order to change from one computer to the other, then you could put the KVM and its cables on the floor somewhere. Another interesting realization was that, in some KVM switches, your USB devices would follow the monitor. So if you switched your view from computer 1 to computer 2, your printer and other devices would now be at the command of computer 2 as well. Obviously, this could quickly make a hash of your files on an external USB drive, and your print or scanning jobs underway on computer 1 would come to a sudden halt as well. There would also be some delay as the second computer re-recognized the USB devices that the first one had just been using. Fortunately, this drawback did not exist in other KVM switch models, including the IOGear MiniView. In that particular device, there were two separate tracks: your keyboard, mouse, and monitor(s) could be attending to one computer, while your USB devices were responding to the other. As I thought further about that, I realized that I might not want all of my USB devices to go the same place. Just because I was scanning something with a USB scanner did not mean that I wanted that same computer to dominate access to my shared USB drive as well. So I decided to take a brief look at other USB switches. There were actually two reasons for this. Besides wanting to be able to control the USB drive separately from the scanner or other USB devices, I would also want USB 2.0 rather than USB 1.1 speed for the external drive, whereas it was beginning to look like some of these KVM switches supported only USB 1.1. A quick search on found an IOGear device (and I was sure Belkin and others would have them as well) that would provide USB 2.0 keyboard-controlled sharing of a USB device among several computers for $30 with shipping. So this option appeared available and affordable. One distinction that I encountered was between two-port and four-port KVM switches. I was not sure what ports they were referring to. In my way of thinking, there were many ports at issue here: USB ports, keyboard and mouse ports, and monitor ports. As I continued reading, it appeared that they meant "computer" when they said "port." Basically, if you were using two computers, you would have two mouse ports, or two monitor or keyboard ports, so you could call it a two-port switch. Although KVM stood for keyboard, video, and mouse, I realized I would probably want audio switching too. I was not prepared to predict that I would be doing audio-based work (e.g., listening to dictation, viewing video) on only one computer or the other. This realization eliminated some KVM switches that seemed able to do a good job at a cheap price, but were built for use in a server room rather than at the desktop. I wasn't sure how concerned to be about USB switching, but I didn't see any units that lacked that option. On the other extreme, as someone pointed out, if the supplied USB ports on the KVM were not enough for all of the devices that I wanted to switch, I could just add a USB hub and connect a boatload of them. The other concerns that emerged, as I reviewed various users' comments, were: (1) some had problems with nVidia-based motherboards, which is what I expected to have on both the primary and the newly forming secondary computer; (2) some noticed video quality or mouse performance degradation; (3) some found their systems less responsive (though apparently not so with USB as distinct from the alternative (serial?) form of connection); (4) other random quirks (e.g., one Belkin unit would treat Ctrl-C Ctrl-V as a hotkey command to switch computers, rather than as a copy-and-paste sequence). Since it appeared that a majority of users were pleased with the hardware, and since I thought it could provide significant benefits for me, I was leaning toward going ahead with a purchase. At this point, within the world of KVMs (after reading users' experiences with the Belkin units), it seemed I had just one or two choices. I had noticed that the IOGear device mentioned above, the GCS1742 (said to be Linux-compatible), was at the top of the list in Newegg's list, in terms of customer reviews: it had received an average rating of four eggs (out of five) from a total of ten reviewers. These weren't great numbers, but they seemed to be the best game in town; hardly any device listed at or Pricegrabber had garnered more than one or two reviews. The only reasonable alternative to the GCS1742 was its sibling, the seemingly well-received four-port GCS1744. It had gotten about the same rating from eight Newegg reviewers; it cost $50 more at the cheapest merchant on Pricegrabber. I was not entirely thrilled at the prospect of more hassles due to my MSI or nVidia-based hardware, however, nor to discovering quirks, quality degradation, slowdowns, etc. Before taking the plunge with IOGear, I considered the possibility of using basic hardware switching after all. That is, I wondered if I shouldn't just buy a bunch of switches and use them to switch each device separately. For $69,, for instance, would sell me a switch that would connect two computers to one monitor. It would take two of those to control both monitors -- unless, of course, I decided that I needed only one monitor for the secondary computer. Then I would need a simple little FujiPlus USB switch for $17 (which, I noticed, had become the alternative for one reviewer after his/her KVM failed!) for the mouse and keyboard. Maybe I could just use a Radio Shack splitter cord to plug the audio into both computers at the same time. I would have to do would be to throw three or four switches every time I wanted to switch computers; but how often did I actually plan to do that? And the hardware approach seemed much more reliable, and easier to troubleshoot: if the USB switch failed, I would just try another one, without simultaneously losing my monitor solution. Having read about numerous KVM hassles (and having seen that no KVM managed to get five stars or five eggs), I thought I could take my chances and buy one and see how it worked. But I hated to spend extra time if it was not necessary. So first, I thought I probably should price out this hardware option and see how it looked in detail. The devices I needed or wanted to switch were, again, the monitor(s), keyboard, mouse, headphones (and possibly speakers), multifunction printer/scanner, and possibly others. Most of these were USB devices already. My keyboard was PS/2, but I could get a satisfactory Logitech 967740-0403 for $15 including shipping. I had not previously realized that you could get USB headphones -- I hadn't had any need for them, and I still had a couple pairs of the regular kind lying around -- but now I saw that I could get a reasonably well-regarded CyberAcoustics AC851B USB headset (with microphone) for $25 including shipping. I felt that I would generally want the audio to go where the keyboard, mouse, and monitors went. (If I wanted the other computer to be playing background music, I could just plug in some speakers.) So I would need a USB switch with at least three ports for keyboard, mouse, and headphones (unless I wanted to buy a hub for this purpose). Of course, if I was going the USB route, it seemed that I could reconsider some KVMs that I had rejected earlier on grounds that they did not have audio switching. But I postponed that review for the time being. Looking strictly at USB 2.0 device switching, the well-regarded IOGear GUB401 ($40 including shipping) would give access to a single USB device for up to four computers (two, if I went for the $30 GUB201). I would have to try it with my USB hub if I wanted my mouse, keyboard, and headphones to share it, assuming they would all work with a hub. Or, for a less expensive solution that had even better ratings, there was the four-port AMC PW-141A for $17 including shipping -- and here, too, I saw people who were using it as a partial KVM solution. It seemed that, if I was going the mechanical route, I would need two or three of those devices: one for keyboard, mouse, and audio; one for the printer/scanner; and probably one for the external USB drive. Of course, I would need those two extra switches even with the KVM option because, as noted earlier, I would not want to make the hard drive and the printer follow the keyboard, mouse, and monitor. So this wasn't really an additional cost of the non-KVM route. Cables and adapters were a bit of a wild card; for instance, they were included with the IOGear KVMs, but not with the Belkins. I had some USB cables but would probably need more. I would have to decide whether to heed the users who contended that more expensive cables were worth their price for video quality. I decided to pass on the cable issue for the moment. In this little investigation, I had forgotten about the part of needing at least a keyboard to be plugged in, if I hoped to have a computer doing reboot-style maintenance in the background. But if I was going to be buying a new USB keyboard, it seemed that I could adopt the hopelessly kludgy solution of leaving the old PS/2 keyboard plugged in at all times, lying on the floor near my computer (in a box, to prevent accidental keypresses by real mice). I wasn't sure if a system would accept a PS/2 and USB keyboard being connected simultaneously, though, so I had to put that speculative solution on hold for the moment. On the USB side, then, I was looking at the cost of a hub (which I already had), plus $17 for the AMC PW-141A, plus $40 for the USB keyboard and headphones. So for a net outlay of $57, I would have the same USB switching functionality as in a KVM, with the various caveats noted above. My net cost for everything on the USB side, with two extra switches for sharing the printer and the external USB drive separately, would be about $90. And this would all be USB 2.0, unlike the IOGear GCS1742, which was still only USB 1.1 capable and, at its best, would cost $183 (though I didn't expect the USB 1.1 part to matter, for purposes of keeping up with low data items like a mouse or keyboard). That still left the question of sharing the monitors. The secondary desktop computer I was pricing did have dual monitor support. That support would not be essential for my purposes, though. In which case, as noted above, I could go with the $69 switch mentioned above, or something like it. For $35, ElectronicsUSA had a video switch that used S-Video, but a quick search turned up no obvious way of converting that to the DVI or 15-pin connectors commonly used or computer video. More promisingly, the Aten VS291 2-port video switch was $57 with shipping from Newegg. Its four-port sibling, the VS491, was $76 at Newegg. (It was only now that I noticed that the switch being sold by KVMS was actually an Aten switch, albeit apparently an older model.) So now the non-KVM option would cost me $114 (i.e., $57 net for the USB solution, and another $57 for the video switch). Of course, as I now realized, if I was going to worry about switching only one monitor, then I could also consider single-monitor KVMs, rather than being limited to the dual-monitor KVMs considered above. A return to Newegg for some comparison shopping along those lines quickly revealed that we were now in another world. By the arbitrary criteria of needing at least 15 reviewers and having a five-egg rating, there were at least a half-dozen contenders, some at very low prices. The extremely simple IOGear MiniView Micro PS/2 KVM Switch (GCS62) blew away the field with 205 reviews (the next closest one had 56) and a lowest price of $20 including shipping and cables. The mouse and keyboard connections were PS/2, however, meaning that I would have to acquire a PS2 mouse or a USB-to-PS2 adapter, and the audio would have to be strictly a separate matter, with its own switch or something. But users' comments revealed that a USB-to-PS2 adapter would not work. So I would have to spend maybe $10-20 for a mouse. Also, I saw no indication that it was hot plugable -- that is, that I could unplug one computer or device and substitute another, without first having to reboot. I wasn't sure how much of a concern that might be for me. The LinksKey LKV-S02SK was another cheap ($30 including shipping), well-regarded (56 reviews, five eggs) PS/2 option, but this one did advertise itself as being hot plugable. Its users had lots of complaints about short cables, and it seemed to me that there were more complaints about ghosting and otherwise inferior video performance. The other primary contenders, in stock, in my search at Newegg, were all from IOGear. Two were in the neighborhood of $130 with shipping, and did not seem to offer much more, for my purposes, than the one that was on sale for $75 including shipping. That one was the USB-oriented IOGear GCS634U, which would accommodate up to four computers and provided audio swapping. The manufacturer's webpage spoke of video signal enhancement, which I thought would probably mean better video than you would get from the cheaper, cables-only models described in the two preceding paragraphs. Users' reviews for this item expressed relatively mild dissatisfaction, as compared to the more passionate tone of some users for e.g., the GCS62, above, where one person said that it got into a mode of rapidly switching between monitors, damaging his monitor. There were no such disasters here; there were just a number of complaints that the key sequence required to switch computers (which I think was also the sequence used for the GCS62) was annoying. My price comparison, then, was between $35 (for unit plus PS2 mouse) plus an audio solution, for the GCS62, versus $75 plus USB keyboard for the GCS634U. I decided my audio solution, for the time being, would be simply to run extension cables from both computers, and to unplug and replug the headphones as needed. I knew that was a kludge, but I really wasn't planning to run many audio applications, so I felt it was sufficient for now. An alternative was to leave a set of speakers hooked up to the secondary computer. In terms of quality, I thought there was probably a reason for the higher price of the GCS634U. I noticed, for example, that one user, commenting on the GCS62, said that it was not suitable for graphics-intensive work as with Photoshop. There were some other graphics-oriented complaints as well. But there were so many positive remarks, and the price difference was so stark, that it seemed silly to start with the more expensive item. So I ordered the GCS62. Before the second computer was ready to go, I used the GCS62 KVM switch for a while just on the primary computer. It worked fine. I noticed no video degradation, no mouse malfunction, no keyboard problems. There was really just nothing wrong with it. The only thing that resembled a glitch was that, if a computer was rebooting, it would sometimes take four taps on the Scroll Lock button, rather than just two, to switch over to the other machine. When I got the second computer up and running, I used the IOGear GCS62 to connect the monitor, mouse, and keyboard to both computers. The connection worked fine. I was able to use the primary computer even while the hard drive on the second one was being booted or repartitioned, or while I was setting up the BIOS or restoring a drive image from the CD to the hard drive, and also while I was booting from the floppy or the CD. All the while, I was able to keep on working away on the primary machine. Thus, I had a situation in which I was using one keyboard, one mouse, and one monitor, with all three of those devices shared between two desktop computers. (I was not able to try it with the laptop, without purchasing a USB-to-PS/2 adapter, because the laptop had no PS/2 ports.) The second monitor remained permanently on, tuned in to the primary computer. Sometimes, while working on the secondary computer, I would try to mouse over into the second monitor, out of habit. The mouse would just stop at the edge of the first monitor, of course; the second computer did not know that the second monitor existed. The keyboard, and the new PS/2 mouse I had purchased for the occasion, seemed to work just fine, as did the monitor. To share other devices, as described above, I had purchased two of the AMC PW-1411A switches. I connected one to the Canon multifunction printer/scanner and the other to an external drive. Those switches, themselves, functioned just fine for both purposes. The printer simply does not work with a computer until I punch a button on the switch to enable that computer to use the printer (or its built-in scanner), and then the computer has full access, with no problems, just as if there were no switch at all. For the external drive, I had previously used a Metal Gear Box (MGB) (by Galaxy, I think), but it would not function reliably with my new computers, both of which were from MSI. So I bought an Apricorn enclosure and used that. The concept, with either the MGB or the Apricorn, was that I could put any IDE drive into the enclosure and then connect it with any computer with a USB cable. I had to be sure to use the Safely Remove Hardware icon in the system tray; but as long as I did that, I could switch back and forth, using the external drive with either computer. I decided, in practice, that I actually preferred having just one monitor available to the second computer. This meant that my right-hand (secondary) monitor was permanently dedicated to my primary computer. So I could switch to the secondary computer and work in that, while the right-hand monitor continued to show what was going on in the primary computer. So when the main computer was done with whatever it was doing (e.g., rebooting), I could switch right back to it and resume my main task. The primary drawback of this two-computer arrangement, which I liked very much, was that it required me to set up and maintain two computers. Running virus scans, downloading updates, doing backups, and other such tasks involved some unwanted hassle. For the backups, at least, I was pleased to be able to use Second Copy 2000, a very useful program that made automatic periodic backups of my drives to the external drive housed in the Apricorn enclosure. (Second Copy 2000 came on the Apricorn CD.) On balance, as of this writing, the arrangement had already made it possible for me to keep steadily at work while the main computer was down for an extended period, while I was upgrading the motherboard (including an RMA for a defective mobo). So this arrangement looked like it would work out pretty well for me.



The Apricorn product I bought was the Apricorn EZ-BUS-DT-KIT USB 2.0 External Drive Enclosure. It worked well, and then it stopped working. Research online indicated that a number of people were having this problem. Apparently a circuit in the machine had been manufactured in China and, like many imports from China these days, had not been thoroughly checked for quality. I contacted Apricorn and got excellent, extremely responsive tech support. They cross-shipped a replacement unit. I have had it in use for a week or two with no further problem.

One thing about these external enclosures: as some other people have commented, it seems you can wreck a hard drive if you don't take the appropriate precautions. You can't just unplug the USB cable from one computer and plug into the other. You have to use the Safely Remove Hardware icon in your computer's system tray (bottom right corner).

One thing I want to praise about the Apricorn unit is the Second Copy 2000 software that comes with it. For me, this program is fantastic. You can set it up to make a backup copy of your hard drive. It will do this hourly, or every two hours, or every day or three days or whatever. It will make a simple copy, or an exact copy ... there are lots of possibilities. I have mine set up to make an exact copy; and since that entails erasing what was on the external drive previously, I have instructed the program instead to move those outdated backups to another folder on a different drive on my computer -- just in case I'm slow in realizing that a valuable file has been fubared.


Since writing the original post, I have added a manual KVM switch for the second monitor. This means that I have to press a button to switch the second one. I could have gone with a two-monitor KVM switch in the first place, except for the problems discussed in the original post. I do not switch the secondary monitor back and forth between computers very often, so I appreciate the option of leaving the secondary monitor pointed at whatever is happening on the secondary computer, while I'm busy doing other things on the primary monitor and primary computer. I'm using a very basic TrendNet USB KVM switch with no keyboard or mouse connected to it, just the monitors.