Hi All, I'm having an issue with my QT app.

Windows 7, 8GB Ram
QT 4.7.1 build in 64bits

I'm converting my 32bit app to 64, but when my app runs out of memory it freezes my entire computer to the point I can't even ctrl+alt+del out of it, and have to cycle the power.

This program was handling memory fine with the QT 32 bit libs. When it would run out of memory it would reach my exception and display my error message and crash the program (not the computer!). But now built with the 64 bit libraries it seems to hog all the memory on my computer and cause the freeze.

I've run it several times with Process Explorer open to monitor the memory usage, and my computer crashes when it gets to about:
CPU Usage = 20%
Private Bytes = ~6Gigs

My questions are
1) Do I need to add code to my program to limit the memory use (I've googled this but can't seem to find how I'd do it)
2) Does it make sense that this is happening, or should my app (or windows) know how to limit the memory usage?
3) any suggestions on how I could further debug this issue?

NOTE: it is not a memory leak, I'm just dealing with huge files and need to make sure it can exit gracefully if it runs out of memory.
I'm not actually sure it is running out of memory, it just seems very likely given the Process Explorer output.
The code is the exact same as the 32bit version.

Thanks for any advice.