Sarasota PC Monitor
Tech Talk (05/01)
Is it Hardware or Software?
by Brian K. Lewis, Ph.D.*
Member of the Sarasota Personal Computer Users Group, Inc.There are times when you are trying to solve a computer problem when it is very difficult to determine what is the source of the problem. You would normally expect the lines between hardware and software problems to be quite sharply drawn. In practice, they often get quite fuzzy. I have a couple of examples I would like to share with you that I think illustrate just what I'm talking about.
The first example involves a brand new IBM computer with a 20GB hard drive, 128MB of RAM and an Intel 700 CPU. It is a very fast machine. However, on initial setup it was determined that there was a problem with the modem. The AOL 6.0 software could not find it. The control panel indicated that the modem was installed on both COM 1 and COM 3. A rather unusual situation for a modem. Even more interestingly, the Device Manager had no modem in the hardware list. It did list two COM ports, 1 and 2. So, the first step was to remove the modem from COM 1 in the Control Panel. Then I ran the diagnostic program in the control panel. That indicated that the port could not be opened. Second step was to disable the second COM port in the BIOS. Still, couldn't open the COM port. Prior experience indicated that this modem might be dead on arrival. However, there was one more step to be taken. Remove the modem from the Control Panel, reboot the system and see if the Plug & Play system would find the modem. No success and now there was no modem entry in the Control Panel. Again, it would seem that this modem is dead and should be replaced.
Oh boy, we get to call IBM service. It turned out that the customer service telephone number that was referenced on the documents provided with the computer did not apply to this particular computer model. Of course, that was after navigating a few press 1, press 2 menus and wait for a technician to respond. On the second number, the response was quite fast. Yes, we did have to navigate a menu to finally reach a tech.
The tech advised us to make sure there were no references to the modem in either the device Manager or the Control Panel. Then shut the machine down, remove the modem from slot 1 and reinstall it in slot 2. That, of course, breaks the factory seal put on the case by IBM. However, the tech insisted it would have no effect on the warranty in this instance. After doing that and restarting the computer, Windows ME reported that it had found new hardware. It then installed the modem on COM 3, IRQ 9. After that, it was a piece of cake to install AOL 6.0 and the owner's previous AOL account information.
Why didn't Windows ME recognize the modem right out of the box. Beats me! But, it appears that this was some software glitch in the Plug & Play system. Either that or something in the motherboard hardware design prevented the modem from being identified by Windows when it was in the number one slot.
My second example involves an older computer with an Intel 233 CPU, 6GB hard drive and 64MB of RAM and running Windows 95. This system has an IDE ZIP drive and a CD-ROM. The ZIP and the CD-ROM were on the same cable connected to the secondary IDE port. Everything was working smoothly until the owner purchased a Plextor CD-RW and installed it in an open bay. He disconnected the CD-ROM and connected the cable to the CD-RW. From that point on, the computer would not read any CD's and the music CD's would not autoplay.
The CD-RW was properly identified in the Device Manager as a CD drive. The make and model were also correct. However, when you looked at it by double clicking the "My Computer" icon, it was identified as a "Removable" drive, not as a CD drive. In fact, when I placed a CD in the drive and tried to read the directory listing, the message I received was "this disk is not formatted. Would you like to format it now?" Windows was seeing this drive as being the same as a floppy drive or a ZIP drive. Removing the drive from the device manager and rebooting the system resulted in no change to the identification of the drive.
The second step I tried was to change the cable connections for the CD drives and the ZIP drive. The ZIP drive was reconnected as the slave on the primary IDE port. Then the CD-RW was the master on the secondary port with the CD-ROM as the slave on the same port. When the system was restarted, all of the drives were correctly identified by the BIOS. However, in Windows, both drives were listed as being "Removable" drives. Neither one would read a CD. Then, I removed both drives from the Device Manager, shut down the computer, disconnected the secondary port cable and powered up again. The system came up as expected with no CD drives. Shut down again, reconnected the secondary cable, restarted, the system came up with two removable drives, and no CD drives. Aaaaaarrrrrgh!!!! (just a little frustration release)
This computer was running the "A" version of Windows 95, which has little in the way of diagnostic software. I had investigated the settings in the Registry. They seemed to be the standard settings for a CD-ROM drive. I also noted that there was no config.sys file and the autoexec.bat file did not have any reference to the Microsoft CD driver. The owner indicated he had been able to access the CD-RW when he booted the computer with a Win98 recovery disk. Finally, a light dawns. I setup a config.sys file with a DOS device driver for the CD-ROM and placed an MSCDEX command in the autoexec.bat file. Rebooting the system resulted in proper identification of the CD-ROM drive as a CD drive. Next, I placed a second CD driver in config.sys and a second MSCDEX command in the autoexec.bat file. With that change, both drives were now CD drives instead of removable drives. However, neither one will autoplay and you have to use the RUN command or Windows Explorer to access the drive to install new software. In the Device Manager, there is no evidence that these drives are using the DOS drivers instead of the protected mode drivers. Microsoft does have a few older CD drives in its references that require DOS mode drivers.
So where was the problem in this case? Certainly not in the hardware. It is probably a glitch in the Windows 95 software installed on this particular computer. This was another problem that might have been hardware related, but was really a software problem. Microsoft has no references to any problem of this kind in its TechNet Knowledge Base or on its Web sources. Neither CD drive manufacturer has any reference to this type of problem. I suspect that if this computer is ever upgraded to Windows 98SE or Windows ME that the problem will disappear. However, there is certainly no guarantee that this will happen.
I would still like to know where Windows 95 was keeping the information that these were "removable" drives. If I could find that, then maybe, the settings could be changed so the drives would function correctly. The problem is that much of the information that is stored in the Registry is done in a coded format that only Microsoft understands. For example, I had a problem with a Microsoft application that wouldn't update. In order to correct the problem I needed to rearrange the alphanumeric characters in a 16-digit reference. However, I had to first get the sequencing information from Microsoft. The revised alphanumeric sequence was then used to find and delete specific keys from the Registry. Only after completing this process could I reinstall and update the software. Obviously, Microsoft isn't telling us everything about the information stored in the Registry. Just remember, it isn't always clear whether a problem is hardware or software related. Check it out both ways.
*Dr. Lewis, a former university & medical school professor, is a computer consultant doing instruction, hardware/software services and system upgrades.
He is available to help you with your home or business computer problems. He does make house calls and can be reached via e-mail at brian_klewis@hotmail.com or voice mail at (941) 925-3047. Note: there is an underline between the n and the k (n_k) in the email address. :
_______________________________________________________________ Copyright 2001. This article is from the May 2001 issue of the Sarasota PC Monitor, the official monthly publication of the Sarasota Personal Computer Users Group, Inc., P.O. Box 15889, Sarasota, FL 34277-1889. Permission to reprint is granted only to other non-profit computer user groups, provided proper credit is given to the author and our publication. We would appreciate receiving a copy of the publication the reprint appears in, please send to above address, Attn: Editor. For further information about our group, email: admin@spcug.org/ Web: http://www.spcug.org/
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