Question Dell laptop emits intermittent series of short beeps accompanied by odd keyboard behavior ?

May 19, 2022
Hello there, I've been having an issue with my aging Dell Precision M4800 laptop that I've owned for maybe 5 or 6 years now. It's been an amazing machine and still works very well (it was originally $3,000 or thereabouts -- bought by my ex-employer and then given to me on departure) so I'm reluctant to replace it with something newer but inferior in performance.

The issue is that now it will occasionally emit a series of beeps while I'm logged in and using it and the keyboard will briefly stop working during that. Eventually the keystrokes will result after a delay, i.e. control key combinations and/or printable characters. Sometimes it appears that the "Ctrl" or "Alt" key is stuck as further keystrokes will behave as if either of those keys is down. Please see this video I captured of this happening:
Here's what I've attempted to mitigate:

  • I "reset" windows to its out of the box state (keeping personal files).
  • I applied all Dell updates using the "Dell Command Update" utility and Windows update.
  • I replaced the keyboard with a brand new one.
  • I replaced the keyboard ribbon cable with another identical one (hard to find, so I had to buy a used one).
  • I re-seated the ribbon cable dozens of times.
  • I disabled my mouse touch pad (It was only working on and off so I suspected a hardware issue with that which I was inadvertently triggering while typing or rubbing against it).

None of these have fixed the problem. Sometimes it will go a few days without presenting, and suddenly there will be a fit of them in a row. I find that restarting the laptop seems to curtail this for a while, like it somehow refreshes the state or "restarts the clock".

Here are the current specs:

Dell Precision M4800
32 Gb SoDIMM DDR3L 1600MHz Un-buffered RAM (it started with 4, but I recently upgraded -- the issue was occurring before that upgrade though).
Intel Core i7-4800MQ CPU @ 2.70GHz, 2701 Mhz, 4 Cores, 8 Logical Processors.