Hello, I bought Heroes of Might and Magic 3 from here, but when I play it on my Laptop it constantly uses 50% of my cpu, which is 100% of one of the cores. This intensive cpu usage overheats my laptop and although I have additional cooling system it is unplayable. I have windows 7 x64 on tha machine. Cans someone help me on that?

I'm afraid this happens with many games, not just this one.

Tried changing the power settings, eg the max battery preset? That will limit speeds but H3 should still be playable.

That does not happen on my Win7/64 system. I don't have a solution for your problem but knowing that it doesn't happen on every Win7 system might help you troubleshoot it.

You might also want to try Heroes 3 HD mod, it replaces the executable, allows for higher resolutions and fixes some common basic bugs and I think it also fixes some CPU overheating issues; here it is:
http://sites.google.com/site/heroes3hd/
P.S. Download the latest version from the Russian version of this site:
http://sites.google.com/site/heroes3hd/rus/download
as the English one has outdated files (game is in English, though).

EDIT: It doesn't actually replace any files, it adds its own so you can safely unpack it into your game directory; you can still run the original executable if you want to go back!

Thanks for the link.

I find that if I play extra-large maps too long in one or two sessions without a reboot, then freezes, crashes, and general slowdowns are much more likely to occur. It's not a big problem for me with this game at all, but if you have problems of any sort, see if restarting your game and/or your computer cleans things out enough for smooth gameplay. Works for me on the slowdowns pretty well.

Thank you for the replays, later I will try Heroes 3 HD mod and tell you if there are any changes. It seems that many old games seem to have this problem (like H2IWclassic mentioned). I installed Rise of Nations and the same thing happened - cpu on 100%. Maybe it's the video card or drivers...

Well, HD did not solve the problem, but it has some new interesting features.