I have a Top Spec Dell Lattitude 830 with 4GB Ram

Video is Quadro NVS140M - 512Mb Ram Forceware 174.31

XP service Pack 3 and latest video drivers etc etc. 

50% of the time when I use Standby, my machine comes back to life but the display won't fire up.  I can tell the computer is on as if I plug/unplug a USB device it makes a noise and the hard drive is working away. There seems to  be no pattern as to when it will/won't work.

The only way to get it back is to do a reboot.

I can't use Hibernate as it doesn't seem to work well with 4GB Ram.

Given I work on multiple projects at once and work in many different offices this is causing me major headaches. 

Any suggestions.