Is it me or does KB:AP crash every 30 minutes?

[Metroplex]

The message I get is along the lines of 'Direct-X call failed' but I think I have nailed the problem, it might me a mixture of what I have:
I'm playing on Windows 7 RC, My graphics card is overclocked and tends to get hot because I have the game maxed at all settings at both in-game menu and Nvidia control panel, the drivers might not be stable, we are in summer in Australia and this also increases the temps... but no matter, I constantly save my progress by pressing F5 key.