XPS 1530 Over Heating after only 4 months, Dell refuses to honor warranty!

I purchased an XPS 1530 fromm Sam's Club auction January 10th 2009, it stated it came with the standard XPS 1 year warranty. Computer arrived on Janauary 29th. Towards the end of May it started overheating and shutting itself down. I went online and added it to my systems( I always purchase Dell and have several). The warranty online showed purchased January 2008 and warrany expired. There was instruction to register the laptop if it had been purchased via retail supposedly to correct the warrany dates, which I promptly did and then I waited the 24 to 48 hours for the update. Well suprise, nothing changed. I then called no less than 4 times and after several hangups and more than 3 hours on hold was finally told it was not thier problem that I need to contact Sams Club. to add insult to injury the last tech(Mike) said next time you will know to buy direct through Dell! Have checked since and Dell has changed my warranty info to Janaury 29th 2009 to May 10th 2009, less than 5 months and still out of warranty. Well very angry I called Sams Club and explained the problem. The girl was polite and said she was aware of this type of problem and would get it fixed and corrected with Dell. This morning I get a voice message froms Sams Club Online which said my warranty starts the day I make the purchase...nothing more just that message? I am really not clear on what they meant, can't call back until monday when they are open again. I know the Sams Club Online auction specifically stated the warrany was 1 year, I even had the Sams Club rep confirm that when I called in. Anyone have any suggestions? I am now going on three weeks with no computer, not using since I don't want to risk damaging any other components.