I'm pretty certain this is an issue with my own PC at this stage and not a general problem with all XPS M1330's that have the 8400M GS video card but I'm throwing this one out there for comment just to see if anyone has any bright ideas.
I've had the XPS for about four weeks now and apart from a single Blue Screen crash on the day after I got it (as it was rebooting after being patched) it has been rock solid. It is still rock solid if all I do is stick to standard PC stuff like browsing the web, posting nonsense on the blog playing some old games and what not. I'd tried playing UT3 Demo on this PC but it felt like playing in molasses so I never played it much, and had much more fun playing that on the XPS 420. However I got both Valve's Orange Box and Unreal 3 during the week and installed them on Thursday. At that point I was running the up to date standard Dell supplied drivers for all the hardware on the device some of which (like the Video drivers) are a couple of months old but nothing is seriously out of date. I immediately had problems with Team Fortress 2. It would run for a bit, allow me to connect to a server and start to wander around but within a couple of minutes the screen would go black and I'd lose all interactive capability with the PC. All the lights were still on but I couldn't get back to the OS at all - even the touch sensitive media buttons and DVD eject button on the top of the keyboard failed to respond. I had to force the device to reset by holding down the power button for 15 seconds.
I checked out Valve's support and found lots of information about hot fixes to solve similar sounding problems when running HL2 engine games on Vista. So I applied all of them (only one was actually applied, Vista told me the others did not apply to my hardware). No joy.
I checked out Nvidia's support site and found a similar but slightly larger list of hot fixes. I applied them and again all but one were not applicable but again no joy.
I then tried reinstalling\updating DirectX with the August update just in case that had been corrupted at some stage. No joy.
At this point I was testing using Portal cos it was easier to get it started and was a bit more fun to play for the 10-15 minutes it would take before it crashed. The crashes are weird by the way - I can start Portal and generally play a level or two before it locks up an delivers me to the Black Screen of Death but if I stop playing it will stay at that spot without crashing for as long as I've left it so far (more than an hour).
At this stage I decided I needed to see if this was a core video driver problem and immediately ran into the traditional problem with laptops - the manufacturers do not release drivers anything like as often as the Video Card manufacturers do so the Dell supplied drivers at V156.55 were well behind the cutting edge from Nvidia ( 158.36 for WHQL certified Series 150 drivers ). Nvidia's own driver packages will not install on most laptops but thankfully the internet delivers an alternative with LaptopVideo2go.com who provide repackaged Nvidia drivers with updated .inf files that resolve that problem. So I tried the 158.36 drivers - No Joy. Note I carried out this exercise four different ways - trying a simple upgrade in place, and then totally uninstalling the video drivers and installing the upgrade and then repeating the exercise using Driver Cleaner to be certain that I wasn't getting mixed up driver components. I also tried to install the 160 series drivers but they point blank refuse to install on this machine.
Just to be certain that this was not a Valve problem I switched over to Unreal 3 and that is an even better demonstration of the problem. I can start a single player campaign but as soon as I get past the very first door on the training level it Black Screens. If I hang about and don't move outside it stays up.
I've since uninstalled every bit of potentially iffy software that I had installed over the last few weeks to no effect and then in a fit of desperation I shut down every service and support application I could on the machine just in case this was being caused by some other rogue process. No joy.
For a laugh I installed Unreal Tournament 2003 earlier and played a couple of Death Match games this morning without a hitch.
The really awful part of this is that much to my surprise all of the games play well on this box before they crash. Now they aren't delivering 100+fps at 1920x1200 but they are fitting a nice comfortable frame rate for casual gaming on a laptop. Certainly Portal would be perfectly playable and a single player campaign on U3 seems to be possible.
I believe I have a hardware problem but I'm at a loss as to what exactly it is - apart from the fact that my PC can't play some high end 3d games. Any ideas folks - should I just send it back to Dell and ask them for a new one? There is plenty of evidence on the web that folks use this particular set up to play these games and I can find nobody else with a problem that clearly matches it.
Edit: I dug a little deeper as described here and then chased Dell for an active resolution - after phone troubleshooting demonstrated a hardware fault Dell sent a technician to fix it and after letting it settle in for a couple of weeks I posted a final update here. The problem was a hardware fault.