Keyboard & trackpad issue

We have an Acer Travelmate 5735 with a keyboard and trackpad issue. Both work in the BIOS and boot selector but don't work in Windows or an bootable OS environment (Linux, Windows PE etc).

We have upgraded the BIOS, reset CMOS and re-seated both cables. Since the BIOS upgrade both devices show in device manager but as problem devices. A USB keyboard and mouse work fine.

Any ideas or is this a motherboard fault?

Comments:

1. I'm not sure how it could be a hardware fault if it works in the BIOS.

Are you sure it hasn't just been disabled or turned off? What error code does Device Manager give?

If device manager shows a resource conflict, look for an option in the BIOS that allows you to reset the Plug and Play device resource allocation.

Its certainly a very strange issue.

2. Device manager in Windows (show hidden devices) gives the error message...

This device is not present, is not working properly, or does not have all its drivers installed (Code 24)

The keyboard works in the BIOS and boot menu, but doesnt work in Windows Boot Manager (select safe mode for instance). The laptop BIOS is very very basic and has no settings that can be changed for IRQ or PlugnPlay.

Booting an Ubuntu CD and neither work only USB mouse and keyboard. Tried to install Windows on a fresh hard drive and keyboard and mouse don't work when booting the Windows 7 DVD.

sounds like a mobo fault to me. In Most bioses you are only going to use the arrow keys and maybe enter. I bet with a keyboard diagnostic running you'll find that even in Windows those key are working and nothing else.

3. Did you recently replace the component. I've seen a couple of times where both are on one ribbon cable. It doesn't make sense that both are bad (at the same time?)

4.We have stripped the laptop down, removed all non essential parts (optical, wireless etc) and tested with just the keyboard connected and then just the trackpad (separate ribbon cables) but still the same.

We tried the function button on the keyboard.

Will try leaving the power and battery out over the weekend but I think it will end up being the motherboard.

Its a day of very strange issues, had an Outlook account earlier on a new computer that was constantly updating the address book, turned out to be the wireless keyboard driver needed updating???