Newly built computer crashing (no crash message)?

This sounds like it could be an issue with the graphics driver. Since you mentioned that windows 7 did updates and the crashing was happening aftwards, it might of installed its own version of the driver for the graphics card. What I would do, is go into device manager, uninstall the driver for the graphics card, reboot, and go to the website www.asustek.com and download the latest driver for that graphics card, reboot, and see if the crashing continues. You should be able to view this information in the Event viewer in windows. Im pretty certain these type of error messages would be logged. You can get their by going to start run and type in eventvwr