doesnt the receipt have the serial number of the system?
When i went and got mine, he scanned the sticker on the system and the UPC on the box.
I've got about 2 more years of the RROD warranty, and I think any other faults warranty, IE DVD drive, wont cover. Thats why people said wrap it with a towel, turn it on, and leave it till it gets the RROD, then send it in to MS to get it replaced.
Thats what I have heard, I think it has to be the same make and model. Last time i checked, there was 3 different ones.