Inspiron 9400 - 7900 Go GS Overheated?

Hey all,

So I have a problem with the graphics card in my laptop, heres what happened.

I was in the middle of a raid in WoW when certain textures started flickering, then from the centre of the screen there was loads on different colours etc shooting out towards the edge, then locked up and had to restart. On the windows loading screens, there were random lines running across, and then when you would expect to see your desktop, nothing, just black.

I rebooted in safe mode, and rolled back the video drivers, rebooted, and all was fine. This was on Thursday. Yesterday no problems, all working fine. Today, the same happens again, flickering textures, splurges of colour shooting out from the middle, and lock up.

I went into safe mode again, but I could not roll back the video drivers.

I then dis-assembled my laptop, and found nearly 2 years of gunk had more or less completely blocked the heat sink on the gfx card side, and half blocked it on the cpu side. So I cleaned out all the gunk, put it back together, but I still have the lines up and down the screen on boot, and it will not boot normally, only in safe mode where I am posting this from.

I also ran the Dell diagnostics on start up, and it produced Error Code 5300:0119 while testing the video memory.

Googling this error code seems to show that the gfx card has overheated.

So basically, do I need to replace the graphics card? If so, where can I get hold of a replacement?

Thanks for reading and any help would be appreciated