Game crashes with the ATI Radeon Mobility X1300 512MB Hyper memory

[Corporal P]

It crashed during gameplay with a message box stating that it couldn't locate the video memory and that the Visual c+++ runtime wanted to close the program in an unusual way when it...
-was a huge map
-was with just 10 or less CIVs
-was moderate numbers of improvement on the map
-was with Bluemarble terrain Hi/Low res installed
ps. I've tried both and even when it was not installed. It would crash anyway.
-was with everything in the graphic settings set high but excluding the box high level terrain
ps. I've tried the lower settings and even that it still crashes.

So, the question is that why does my system still crash? Does my system not meet the graphic requirement (pls refer to below)?

My computer:
NB Acer Aspire 5542
Intel Centrino Duo
Intel core Duo 1.66
1GB DDR2 RAM (512MB Dual channel)
ATI Radeon Mobility X1300 512MB Hyper memory

Thank you very much. I appreciate every answers and comments.

 

[crunch]

Which game? Civ4 or Warlords?

All patches applied?

How does it crash? Always in the same moment (i.e. by repeating your steps you can consistently crash at the precise point)? Or rather it simply crashes from time to time, allowing you to reload and play a few more turns before crashing again?

Any other mods used?

Notebook blazing hot?

Running tons of background applications?

Ini file settings SetMaxFrameRate=30? (If not, do so.)

 

[Corporal P]

-Warlords

-Yes. It's up to date.

-Put it simple, when it has moderate numbers of graphic to display such as unit, improvement and terrain. It crashes by simply close it self and return to desktop with 2 message boxes
1. "Failed to allocate video memory. Please try reducing your graphics settings. Files:\Source\main\Civilization4\SDKs\Gamebryo2_0\Core2:bs\NiDX9Renderer\NiDX9VBManager.cpp, Line:1019"
2. "Runtime Error! Program: ...mes\Sid Meier's\Civilization4\Warlords\Civ4Warlords.exe. This application has requested the Runime to terminate it in an unusal way"

-Yes, my own mod. But I think I pretty much knew what I was doing. Didn't touch any other files except those XML needed for Units, CIVs and Civilopedia modification.
PS. No bugs or errors and if it had been one, it wouldn't contribute to the crashes. I think.

-Yes, you could say "Blazing hot" coz it's in the end of summer here in NZ. And, this game is so addictive if you know what I mean.
PS. I've tried to run the program with the same settings and save while my notebook is cool or has been cooled down, and it still happens.

-Nope, closed every single one of them and even checked with utilities like process manager and such. Oh, and I also recovered some of my system memory back using memory utility.

-Not, yet. Will do that. By the way, where is the file located?

Thank you very much for you help, Crunch. Cheers!