Wow this is yet again an example of a poster not giving any sort of useful information.
I assume now he is talking about memory not showing up ont he video cards control panel where it says "video memory" with all the debate about windows xp seeing over 4gb in windows xp I think that has us all confused what he's asking.
Poster you need to put relevent information.
What type of video card, motherboard, os, and mainboard memory do you have?
Where are you looking exactly where your not seeing the memory, and what exactly do you expect to see there that you don't?
As far as crashing goes, please put more of a description of the problem up, I am going to assume the amount of memory not showing up, has nothing to do with crashing.
Make sure you get the latest and greatest drivers for your mb and your video card for the appropriate companies website, that may help fix any issues. Also, another thing to look at would be swaping out the card with a known good to eliminate that. Go to BB or CC or wherever get a basic card to test with, if that does not crash your system, most likely it is your current video card and it should be rma'd.
Just my two cents.
Thanks