XPS M1710 - Corrupt Post screen and no Windows

Howdy folks,

A bit of a weird one this, and I can't really find anything that matches this when I trawl Google.

I have a Dell XPS M1710 which I've owned for about 3 years now (from new). I use it when I have to go travelling, but still play a few games etc etc. It's got the standard NVIDIA GeForce Go 7900 GTX with 512MB DDR memory in there right now. The only thing I've done to it (over a year ago now) was to add another 2GB of RAM to take it to 4GB total. And I've had the fans out too because they became so blocked up with dust that I was getting about 30 mins before it overheated and turned off.

So, yesterday I had it turned on, but it was just sitting idle whilst I was playing SC2/WoW etc on my main desktop PC. Then, when I looked over at it, I noticed that the screensaver (standard Windows 7 wavy line one) had frozen, and there were little red pixellated dots all over the screen. Upon moving the mouse, hitting keys, etc etc I realised that it had locked up totally .. didn't look good at all!

Now when I boot it up, the initial BIOS Post screen (with the big DELL logo and Intel Logo in the bottom right) is all corrupted and messed up. You can see the 2 logos (Dell & Intel), but you can also see the background 'masks' that they are on, and the remainder of the screen is full of short, vertical, green lines in clusters. It kinda looks like the Matrix 'code'.

However, when the little Windows 7 animated logo appears (after having moaned about my PC not booting properly last time etc etc), just before Windows itself launches, there is no corruption on the screen at all ... everything looks fine. Unfortunately, as soon as the logo disappears, the screen goes black (but it's still 'active', if that makes sense. The screen doesn't turn off, it's just a black image being displayed) and Windows never boots.

If I enter the BIOS setup screen, that too is all corrupted and messed up. I can see all the options to be able to select them, that's fine .. but you can see that it's corrupted (white lines/text are all fuzzy & misaligned). However, if I boot in "Safe Mode" (using F8 at boot), it goes into Windows with no GFX corruption and everything seems fine. So now I am really confused as I would have thought that a dead GFX card would manifest itself in all areas, especially the more GFX-intensive ones (than the BIOS screens) like safe mode!

As above, my initial thoughts were that the GFX card has died as that would be the only thing to explain GFX corruption in the POST screen. But then Windows Safe Mode, the Windows logo and the Windows 7 installation GUI (repair function etc) all appear fine, with no GFX corruption at all. So maybe it's some kind of driver issue, virus?

Here's what I've tried so far: -

1. Turned it off and back on again :p
2. Left it off for 3 hours - Still had the problem
3. Removed AC & Battery, held power button for 2 mins, tried again - still had the problem
4. Tried the Windows repair function - still had the problem
5. Reinstalled GFX drivers via Safe Mode - still had the problem

For some reason my PC simply will NOT recognise the Windows DVD in the drive and boot from it. I even turned off ALL other boot devices, so the Windows DVD was the only option, and it just tells me that there is 'no bootable drive' blah blah. I can't re-install Windows from Safe Mode as it says it will only work from 'Normal Mode' ... and I can't get into 'Normal Mode' right now. My next option is to try and copy the Windows DVD onto a USB drive, and see if I can boot the installation process from there. I am yet to find a way to boot to a DOS (or equivalent) environment that will allow me to run the installation from there.

As you have probably gathered, I am running Windows 7 32-bit :)

I hope that all makes sense. Sorry for the long post, just wanted to get as many details in as I can. If the GFX card is dead, can I get a new one? Can I get a better one even?

Cheers for any help/advice/opinions.

Orias