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My computer's PS2 ports are destroyed (mouse and keyboard), they can't detect any keyboard/mouse that I plug into them. I tried to let a local technician repair my motherboard but he failed miserably, he even busted 2 out of 4 USB ports found in the back of my motherboard. So, I ended up using a USB keyboard and mouse. The problem is, every bootup the computer makes these annoying beeping sounds. These are the sounds that are made when you are constantly pressing a key on your keyboard, what's weird is that I am not pressing any key on the keyboard. The beeps still happen even if I disconnect my keyboard.

Before an OS is loaded, there are delays before a key pressed is detected. BIOS setup is so slow (i.e. it takes a while before the selection/cursor is moved down to the next option when pressing the down arrow key) since I think the keyboard controller (or whatever) is being flooded with key presses from a non-existing keyboard. The beepings stop when an OS is loaded (when the Windows logo is displayed on Windows XP and Windows 7, when grub is done loading the kernel for my Ubuntu live CD.).

How do I fix this problem? Thank you.

Motherboard Brand/Model: Epox 9NPA3 Ultra

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up vote 14 down vote accepted

I don't mean to be the voice to gloom, but I think it has had it. It could be a short somewhere in the port housing itself or an issue with the PS/2 controller leading to the BIOS thinking it is constantly receiving keystrokes.

Alternatively it could be a BIOS error code.

Seriously, just replace the motherboard, they are not worth repairing anyway.

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I agree. I think that would be the only option. – James T Aug 20 '09 at 15:21
Motherboards definitely fall into the not user servicable category. Throw it away buy a newer, shinier one. – Col Aug 20 '09 at 15:22
It's a wonder it's working at all. There's no telling what else is damaged and only partially working ready to fail at the most critical moment. Retire the poor thing. – salmonmoose Aug 21 '09 at 4:06
I think I'll just have to buy another one, this is a very dated system anyway. I'll upgrade as soon as I have the money. Being in a third world country, that won't be too soon I'm afraid. :) – Ramon Marco Navarro Aug 21 '09 at 13:40

You might want to check if the beeps fall into any of the POST beep code errors. Can you give more details as to whether the number of beeps are consistent across boot-ups, long or short beeps etc.? Might help track down the error.

Also see for explanations of some beep codes.

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It is consistent across boot-ups. It has a different "sound" from the POST beep code errors that I have encountered before. As I have said before, it sounds exactly like when someone or something is pressing a key nonstop. They are very very short but run continuously. I'll have to add that the beeps still happen even if I disconnect my keyboard. – Ramon Marco Navarro Aug 20 '09 at 15:31
Just thinking aloud. Perhaps something wrong with the keyboard controller? Not to sound too draconian, but is flashing the BIOS software an option? If you're thinking of buying a new one, might as well give this a go. – Ramesh Aug 20 '09 at 15:45
I found out that I already have the latest BIOS so I reflashed it but it didn't fix it. I even tried flashing to a lower version of the BIOS. – Ramon Marco Navarro Aug 20 '09 at 15:51

The problems with the PS2 ports happend to me too but without the beeping sounds. After almost a year of searching people to fix it I got tired and I bought a new motherboard.

I know it's not the best answer but it's the truth

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Just to put something different here (the easiest solution would be to just buy another motherboard)...

You have a strange issue that I haven't seen before. With a meter, I would check the PS/2 signals including Keyboard Clock and Data to see what levels they are at. One of the signals could be stuck low.

If the PS/2 connector is the issue, then removing it would be difficult unless you have a solder pot or a hot soldering iron with a solder sucker. You could disconnect the connector from the main board by removing any discrete series elements in between the input and the controller such as a resistor or ferrite bead with a soldering iron.

Some PS/2 bus information is here:

I'd also look at the BIOS to see if you can disable PS/2. At least on one Super I/O am familiar with, it would be a matter of some I/O Port writes.

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This sounds like too much of a hassle, plus I don't have a multimeter. :( I'll just have to buy another motherboard. – Ramon Marco Navarro Aug 21 '09 at 13:43

Those beeps are normal when BIOS detects something wrong. If you have a PS2 port, you must have an old mainboard.

However, you could enter BIOS and see if you can set an option like: Halt on systems errors. Usually you can choose what errors to halt on. Just disable Mouse and Keyboard errors... If you know what mainboard you have, you might even be able to check the manufacturer to see what beep means what! ;)

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The system doesn't halt while it is beeping. – Ramon Marco Navarro Aug 20 '09 at 15:50
Doesn't have to be old to have PS/2 ports, I see new computers at Best buy with them. Granted not all do, but some. – Joshua Nurczyk Aug 20 '09 at 16:35
Does not have to be indeed! ;) But usually is. And sure it does not always halt, just the same as it does not always continue! Depends on the severity! :) Memory errors! :) – Aaaaaaaaaha ERLEBNIS Aug 21 '09 at 8:39

Sounds to me like you should disable the ports in the BIOS and possibly purchase another PCI USB card for the pc. (of course a new machine might make all this mute) but I'd put another 4 USB slots into the machine disable the PS/2's via the Setup and that should eliminate any "ghost keyboard" signals from a shorted out part of the board.

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I don't think my BIOS setup has the disable PS2 option. :( – Ramon Marco Navarro Aug 21 '09 at 13:42

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