Could be a problem with data or clock signals. With just keyboard plugged in, does the num lock, caps lock or scroll lock LED's turn on if you push those buttons ?

Horun wrote on 2023-07-22, 17:43:

Could be a problem with data or clock signals. With just keyboard plugged in, does the num lock, caps lock or scroll lock LED's turn on if you push those buttons ?

Nope, only the quick blink at boot

Not that I've ever seen a laptop with the option to disable external PS/2 devices, but might be worth trying the Config→Reset in the BIOS and going through all the settings* just in case there is one?

* Never seen, never mind used, a 701 and I can't find an user manual for it either, but apparently it has two separate setup utilities in ROM (F1 at power on vs Fn+F1 "in a plain real mode OS") and may or may not have an external setup software included with the "general utilities" driver, like some variant of Ps2.exe?

Good thought Ryccardo, maybe something needs be turned on in the BIOS. Here is the repair/tear down manual with some Diagnostic mentions.
Yeah no real User guide found for a 701c...

The FN+F1 shortcut opens the BIOS setup WHILE the operating system is running, I never seen something like that before and it is extremly convenient.

Here I made a imgur post with short video of the BIOS opening while OS is running and also the four pages of the BIOS setup. It is in italian but I can affirm that nowhere there are references to PS/2 settings. There is a page that it is enabled while the MultiPort is plugged in but it's for change the resource settings of the other ports.

While it is booting F1 opens up this page

from where the same BIOS setup from before can be accessed but also the diagnostic utilities, I did the systemboard one and no issues got detected.

Contrasto ottimo 😁 😁

Yeah, out of ideas here, maybe try turning off the trackpoint but I bet absolutely nothing would change (it's supposed to work the opposite, external mouse blocks trackpoint)...