It may be slightly more complicated to return an item on line due to warranty issues, but if you have one, it shouldn't be impossible. I'm more inclined to think it may be the display itself and that may not be fixed by an upgrade. I might look into warrantying it and how complicated that might be, prior to doing any upgrades. I'm not sure if upgrades void the warranty (they shouldn't) but I could see a vendor trying to point at that issue, and saying it caused the problem (if they even know to do that). If you bought it off ebay or something, I hope you used paypal in case you need to resolve a dispute, but if you purchased it new, from a reputable vendor, warranty/repair should not be so difficult though it may take more time....
Best of luck,
Anna