ST2210 monitor has a constant white screen.

Hello, i've had my Dell ST2210 monitor for a couple months now but it just recently messed up while playing a Playstation 3 video game on it. The problem is that it has a constant white screen from the moment i turn it on, it won't even display the menu when i press the button on the side of it. When i press the lower two buttons on the side the screen will flash black for a second then automatically go back to the constant white screen. This is a problem with the monitor itself, i've hooked it up to three different computers and a PS3 system but nothing will help it to display anything but a constant white screen. I've had this monitor for around two months now, it's been turned on around twenty times for 1-2 hour intervals and i havn't had a problem until now. Also, it was purchased from Amazon. I know i have a one year warranty on this Dell ST2210 monitor because it said so on the Amazon website when i purchased it but a problem stands in my way, i don't know how to go about getting it repaired under the warranty. I need help with this, a simple step by step guide and what information i'll need to provide will make all the difference for me. I know that there's not a Dell service tag on my monitor and i think that's pretty much required for the warranty repair service. Is there any other information that i can provide in place of the Dell service tag to get a warranty repair for my Dell ST2210 monitor? Thanks in advance, i'm really panicking right now with the thought that i'm out of luck and out of my money used to purchase this monitor.