My computer stopped booting normally 3 days ago. Here are the particulars:

  • The computer is a Dell Optiplex 840 with 1 MB RAN and 40 GB hard drive.

  • I have Windows XP because I have legacy software that can't be upgraded.

  • I have a USB keyboard and mouse and a Trenonet USB HVM switch (for using another computer).

  • We had a thunderstorm the night before. I heard a click from the speakers. But the computer kept working.

  • Now when I start it, I see the following in sequence:

--- The Dell startup page
--- The Windows XP startup page
--- The mouse and keyboard lights come on
--- A blue screen with a long error message on it, but it lasts for less than one second, so I can't read it. All I can catch is "Windows failed to start because"
--- The mouse and keyboard lights go off.
--- The Windows Failed to Start recovery page appears. I have no control to change the settings.
--- The Dell startup page reappears. The cycle repeats. I have no control to cause boot from CD.

Here is the weird part: I can get it to boot normally with the following procedure:

  1. Unplug the keyboard from the HVM switch while the above is going on.
  2. Let the Dell startup page report a keyboard failure. It stays there.
  3. Turn off the computer.
  4. Plug the keyboard back in.
  5. Turn on the computer after waiting 15 seconds.
    It starts normally.

The keyboard works perfectly while the computer is running. I am using it now.

What I don't understand is how this made anything different.

I can't eliminate the HVM from the system and boot normally because there are not enough USB commectors on the back to plug in both the computer and the mouse. The computer originally came with PS2 keyboard and mouse, but I upgraded years ago to use a PS2 KVM. I replaced the KVM with the HVM when the PS2 keyboard failed.

I have made no changes in the hardware configuration in the past year.

4 Years
Discussion Span
Last Post by MidiMagic

Replacing the keyboard did not cure it. It does exactly the same thing with a new keyboard.


This is getting wackier and wackier:

I noticed that the HVM is a Trendnet device, not a Trenonet (as posted earlier). The D looks like an O. I have an LED lantern in here now to work on the system.

  • I took off the HVM and added a 4-port PCI card, plugging the mouse into it. The computer did the same thing. I discovered that I could unplug the mouse and plug it back in, and the computer could find the mouse. But the keyboard still did the same thing (plugged into the original USB port).

  • I determined that the original USB port is not providing power properly. So I plugged the keyboard into the new USB card. The BIOS can't find it, and reports a keyboard error. Windows starts, and I then get control over both.

But I need the HVM. I reconnected it. It works with the other computer, but now it won't initialize the keyboard on this computer unless the other computer is on and I switch the console to the other computer and back.

To get the other computer to work with the HVM, I had to plug an extra PS2 keyboard into the PS2 port on that computer. The computer boots with the PS2 keyboard (the BIOS uses it) and then automatically finds the HVM and switches over. But it does not find the HVM without the PS2 Keyboard being connected.

I am going to move the PS2 keyboard to this computer and try it. But I have to log off to do it. Andf if it works, the fun part is finding another PS2 keyboard that works.


It does start correctly with the PS2 keyboard. The BIOS and Windows start normally, and I have instant keyboard control on the USB keyboard through the HVM.

But now the other computer will not start at all without the PS2 keyboard. I get the old oxymoronic error message:

"No keyboard found. You may have to replace your keyboard. Press F1 to boot."

So now my task is to find another PS2 keyboard. It's a kludge, but it works.

I have some more testing to do. I still do not understand why it worked after that strange startup sequence of unplugging the keyboard.

Edited by MidiMagic


Let's say it DID start normally with the PS2 keyboard. I shut it off because I had something else I had to do for about an hour. When I got back to it, it was back to the original behavior again, except that I don't have to unplug anything - just turn it off, wait 15 seconds, and turn it on again.

So there is some kind of delay. I wonder if this is a weird form of power supply failure. That brings up another problem, which gets a separate topic.


I figured it out. The CMOS battery is dying. That is the only thing that can explain the time delay. What fooled me was that it worked when I tested it right after I made each change. But then it quit working later.

I didn't think of this because the "brain" who sold me the computer 8 years ago thought that they weren't putting batteries into desktops anymore.

There is a place in the service manual (which I just got on line - it was not included with the computer) on how to change the battery. So I should have this fixed by tomorrow (when the store I get my batteries from is open). There is nothing about the battery in the tiny book I got with the computer - I guess they expected it to be obsolete before the battery would need to be changed.


Replacing the keyboard did provide a an additional benefit. I had rubbed most of the letters off the keys of old one. Why can't they mold the letters into the plastic, instead of just sticking on decals? They used to.

This is the 4th keyboard I have had for this computer. But the failure on each one always involved the cable where it enters the keyboard (probably because I move the keyboard to the side when I need desk space for writing). Of course, the one I just replaced had not failed.

Edited by MidiMagic: Additional thought


What's with the Daniweb system? I used the BACK button to return to the page I had come from after posting and editing the post, and I got a message asking iof I wanted to leave a page with an unsaved post. I clicked no, and then clicked save, and it gave me a second copy of the unedited version of the post.

Don't you support "tree" browsing anymore? I always use the BACK to go back to where I came from before moving ahead again. Are you expecting me to use the "bull-ahead" method (where I go to a new copy of the menu when I finish a task, ande continue from there)?

This is the post that was the duplicate. I had to put something in it.

Also, your header and footer cover the text box at times. Why doesn't the scrolling exclucde the header and footer, instead of scrolling text under it?

Edited by MidiMagic: duplicate post - I changed it


Midi, it would be churlish of me to offer a solution to your problem. Cos you're having so much fun, and further, investigation is a great source of (self) learning.
Besides, I don't have one...
Okay, I think your BIOS sucks... I might try flashing it if it was mine.
Ha... and then the whole page loaded (freaky delay), I read up and saw that you had fixed it.

Edited by gerbil


It's not fixed yet. I strongly suspect the battery, but until I actually have a new one in it, it is just the best theory I have.


I replaced the battery and it started working (after I reconfigured the BIOS 3 times).

The reason I had no keyboard control of the BIOS was that it was expecting a PS2 keyboard. I plugged one in and got control of the Bios.

Now, three months later, we had another power failure, and it quit working again. It now also won't start windows from the installation disk.

That blue screen came up again. This time, it stayed put (when I had tried to start from the installation disk).

I finally got the code at the bottom of the blue screen. The rest of it had suggestions of things to try (most of which are not available on my bios).

The code is:



Well that's it. The motherboard was damaged. The computer is officially dead.

I found someone who could port the software over to another computer without needing the original websites.

I am sadly marking this solved.

This question has already been answered. Start a new discussion instead.
Have something to contribute to this discussion? Please be thoughtful, detailed and courteous, and be sure to adhere to our posting rules.