Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Possible Duplicates:
Is it possible (yet) to use old laptop TFTs as extra monitors?
Can I use my laptop as a second monitor for my desk computer?

I've an old 15" XP laptop, it's just lying around as it's useless in this day and age (How useless? Try a 400MHz CPU, 128MB RAM, and a 3GB HDD).

I just saw this post about the exact same topic, but that thread is regarding Linux. I'm running Windows.

share|improve this question

marked as duplicate by alex, fretje, ChrisF, Troggy, BinaryMisfit Oct 5 '09 at 16:06

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

There's also this:… :) – alex Oct 5 '09 at 13:38
Actually, this one is even better:… – fretje Oct 5 '09 at 13:49
up vote 2 down vote accepted

MaxiVista or ZoneScreen would be worth looking into.

share|improve this answer
I just bought MaxiVista, works fine with a wired network connection. With wireless, if you're on the edge of the range, each time it drops out, your main monitor will flicker as you change resolution, and the windows come back to the main monitor. – Martin Oct 5 '09 at 13:54
There is also SpaceDesk for free. – niutech Dec 24 '15 at 7:42

I have had success using the freeware application Synergy. Of course, your mileage may very, but it worked for me extending Windows XP desktops across two PCs.

share|improve this answer
I use Synergy, too. But it doesn't provide a way to use another PC as a secondary monitor. It provides keyboard and mouse of the "host" to the "guest" ;) – släcker Oct 5 '09 at 14:31

Not the answer you're looking for? Browse other questions tagged or ask your own question.