Try an external monitor. And extend that warranty. Some makers allow that but have a 30 day waiting period before you can make a claim.
CROSS POSTED AT http://www.bleepingcomputer.com/forums/t/580985/dell-xp2720-screen-problem/ so I'll suggest this and have you watch bleeping.
Hi,
I had my dell xp2720 on yesterday evening as normal, just checked e-mails after work then exited and put into sleep mode. Woke it up an hour later and the screen is almost unvisible with black banding all over it (changes colours when I move mouse over it), I can see it working in the background but I can't get this huge banding etc off the screen, it tends to flicker, change colours etc. At one point in did go away with very minor banding visible, but when it was turned off and back on again it all came back.
I have tried taking power supply out, holding power button for 30 seconds etc and re-booting but still the same. I would guess it's a screen issue as I can still see all my files on the desktop just about through the banding.
Unfortuantely its now 15 months old so just out of warranty.
Any help would be appreciated.

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